AirNav Systems Forum
AirNav RadarBox and RadarBox24.com => AirNav RadarBox and RadarBox24.com Discussion => Topic started by: oceans777 on January 23, 2009, 02:27:14 AM
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I recently bought the new ADS-B antenna from DPD Productions and have it mounted on my roof, about ten feet above the rooftop. Absolutely outstanding antenna for Radar Box, it gets way better coverage just running into my 45 feet of LMR-400 than the three other antennas I have tried using with the mast-mounted Elad Pre Amp. I have now just taken the pre-amp down completely as this antenna works better without it.
Link:
http://www.dpdproductions.com/page_vhf_air.html
Scroll down to very bottom of page for pictures and complete info on the antenna.
I do not know if he ships out of the U.S.
Cost is about $86.95 and I have had numerous email exchanges with Dave, the owner of DPD and he is very responsive and really knows antennas. I also have his LP Miltenna for UHF and it too provides amazing performance.
For ADS-B before I never could "see" below 6500 feet before and am now seeing down to the runway at close airports and as low as 500 feet at KLAX, despite the mountains all around me. Traffic increase is big and range is much improved.
I'm not affiliated with DPD in any way just passing on a great product finally here in the U.S. that doesn't cost a fortune or need amps, etc.
Previously I have used the RadarRama, the 1050 antenna and the very expensive MyDEL BS1100 all mounted at the same height, all ran through pre-amp. Results varied from ok to poor. (I still cannot get any support for the Elad pre-amp or diplexer, short of sending them to the U.K. despite the $365 price.) Wish I had found this antenna before shelling out a fortune on seriously over-priced, underwhelming antenna systems and pre-amps that somehow start rusting inside after a week in Southern California with no rain! Sorry - end of rant. :-)
Just passing this along - hope it's helpful for anyone having trouble finding antennas in U.S.
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Thanks for that. Looks ideal for our use. Good amount of gain on there. as well. Just need to sort out how to get one to the uk.
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Hi oceans777
It seems that You are very glad with Your new DPD antenna. Good !
Could You please post a screenshot of a polar diagram with the Mode-s Sinal Maximum Range to apreciate this ?
Thanks in advance - Juan
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Juan,
I sure will - my Mac Book Pro is at Apple for a new logic board so it may be a few days but I will post soon as back online with it.
Note that I live deep in the LA mountains to the north with high ranges all a round me so it's not going to reach max mode-s ranges by any means and the polar diagram won't look like those in unobstructed areas but it's much improved over my previous. I will find some older polars and post those too.
Should have the computer back early next week and I will set up on the other laptop meanwhile but it's a little slow for RB.
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Spikem,
I checked with DPD and they do ship to the UK. Very well packed too, so you should be ok.
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To anyone buying from the USA. Note that customs may charge VAT to the carrier. If the carrier is the post office they will charge a handling fee for paying the VAT up front. I recently paid £8 handling fee on an item on which the VAT was £3.
Tom
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I have been given a quote of $126.45 (around £93) inc postage. They will send you a paypal invoice for payment. Looks very promising.
spikem
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To anyone buying from the USA. Note that customs may charge VAT to the carrier. If the carrier is the post office they will charge a handling fee for paying the VAT up front. I recently paid £8 handling fee on an item on which the VAT was £3.
Tom
It's worth pointing out that amateur radio equipment and accessories are zero rated for duty, but not for VAT of course, so just in case customs try to get you for duty ensure that you get the sender to specify Commodity Code No. 85299040000 to ensure that no duty is charged.
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HI Guys I also contacted DPD and found them very helpful in answering my questions etc etc. Anyhow I have an aerial enroute to me in Northern Ireland. Paypal invoice as discussed and like Spikem a cost of $126.45. DPD advise, "we send it as if it's person to person, and say it's a ham radio antenna. We can email the receipt and there's no commercial packaging".
I'll keep you posted on progress on both the arrival and once I get a volunteer to have it erected and it is operational.
John
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Hy guys, I also have placed an order for this antenna & awaiting delivery, will post on here when up & running. Spoke with dave at DPD and he says they are selling like hot cakes at the moment so delivery could be anything up to 2 weeks. looking forward to the results.
cheers all Peteeds.
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Hi Guys
Mine is also on its way, but I am in a bit of a dillemma over the cable and connectors.
As the low-loss cables are quite thick I am wary of using a sma plug directly on the cable at the RB end or an Nplug to sma adapter as I have visions of this damaging the RB sma connection on the circuit board at some point. One way around this is to use a fly lead from the RB to the connector on the cable.
Has anyone done this, what cable was used and was there any significant loss involved?.
spikem
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Hi Spikem
I bought my cable assembly from Airbandonline, and they supplied a flylead from the Westflex cable which works a treat - no idea what the flylead cable is, though. Pic attached.
Rod
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Thanks for that Rod . I will take a look.
spikem
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Does anyone know, or can AirNav tell us, what cable rating is used in the supplied aerial?
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Spikem - suggest you speak to pete at at http://www.garex.co.uk/
Absolutely nothing he doesn't know about aerials and cables and I can thoroughly recommend products, services and prices.
(No connection with me whatsoever)
JB
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Hi
My supllied attenna lead is maked RG-174.
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I ordered from Rocket radio, Solid State Electronics and Westlakes on the 22/01/09 all arrived by yesterday.Total cost so far incuding 2x 20 mt of westflex w103, all fittings, etc is (don`t tell my wife, please) £224.57. Just waiting for the guy to come and rig the 2 aerials.
Sky Scan DX V1300 Discone Radio Scanner Antenna Aerial
SSE-1090SJ mk 2 ANTENNA
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hello.
just a query regarding cable type i have 50 ohm cable comimg from outside antenna to my radar box inside in house.i know this has been brought up before and i have looked at websites regarding cable type and length from antenna to radar box.but the thing i would like to know is rg 213 or 214 better and how far can u go with out loosing to much recption.i am moI ordered from Rocket radio, Solid State Electronics and Westlakes on the 22/01/09 all arrived by yesterday.Total cost so far incuding 2x 20 mt of westflex w103, all fittings, etc is (don`t tell my wife, please) £224.57. Just waiting for the guy to come and rig the 2 aerials.
Sky Scan DX V1300 Discone Radio Scanner Antenna Aerial
SSE-1090SJ mk 2 ANTENNA
I ordered from Rocket radio, Solid State Electronics and Westlakes on the 22/01/09 all arrived by yesterday.Total cost so far incuding 2x 20 mt of westflex w103, all fittings, etc is (don`t tell my wife, please) £224.57. Just waiting for the guy to come and rig the 2 aerials.
Sky Scan DX V1300 Discone Radio Scanner Antenna Aerial
SSE-1090SJ mk 2 ANTENNA
ving my antenna up higher next week when weather improves and hope it will soon.
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Hi shannon, I`m a numpty on the technicals, but try Henry at,
http://whwestlake.110mb.com
he was very patient and seems to come recommended.
The chap rigging mine has just phoned, so hope to have them up soon.
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Quick question guys: I already have the ELAD setup, does this antenna integrate into my existing setup with the masthead preamp? Or does the cable go directly from the antenna to the box? If so, then what connection adapters do I need. My current cable is 13 meters long. Whats the best configuration for me?
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Hi all of the above,
following some earlier postings here, AirNav puts it to the customers risk, should a RB suffer from harm when opererated with another (outdoor) antenna, rather than the one supplied with RB itself.
Electrostatic Discharge (ESD) due to an outdoor antenna whose design does not consider preventive measures regarding this phenomenon supposed to be the reason for this (AirNavs) consideration.
A proven precautionary measure against the above could be realized by an antenna design that applies “DC Grounding”. (Meaning the “radiating" / "active” element “tightened to ground” in terms of “DC” at its base [outer connector] the RF but remaining unattenuated on its further way via the antennas inner connector / coaxial cable to the receivers input finally. Electrostatic charges developing are thus “bled to ground”, the latter of course to be provided by connecting the antennas (metal) base / foot to an earth ground (house earth) by "proper means".
Now the specification of the antenna that this posting is pointing at unfortunatly describes :
DC Grounded (as) : A metal ground plane is not needed with this design
just indicating, that this antenna's, others than a “groundplane-” / “discone”- antenna's design, does not require the typical “radials” or metal “ground plane” (also refered to as “counterweight”), which obviously has nothing to do with the “DC Grounding” described before.
No possibility either, to ground the antenna itself by means of its mast mounting, (as a "primary" measure against ESD) the foot / base not being of the metal type as usually found.
Not but a problem so far, as that could be realized at the connectors (end of pigtail) plane.
Beside of the above, specs appearing very impressive concerning a “9dbi” gain. Would be worth to compare with other antennas by means of plotted diagrams if could be performed by a user ? Personally I do not believe in such a spec too much. (More a theoretical / calculated figure, and a lot of "believing in" as is common to antennas.)
Another link, now and then refered to in this and the “other forum” leads to an antenna, also dedicated for a 1090MHz operation, that by its specification / construction / description takes Electrostatic Discharge into account, making use of a “DC grounded” design indeed:
http://www.ssejim.co.uk/26-sseads1090sj.htm
Would be interested to listen to AirNavs comment on the above subject, and NO: its not only me that does NOT consider lightning protectors, surge protectors, DC- Blocks and mast-preamps to be a preventive measure against ESD hits.
The protectors "firing tresholds” could be well above such a limit, that ESD already might have done harm to a receivers input circuitry (even by slowly detoriating its specs over time).
A preamp may protect its successing receiver, but be a victim of ESD itself if not protected (internally or externally).
Regards
Karl
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Is that a yes or no then?
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Flightchecker - I think the points you make are valid. Personally I get the impression that RB is very much a "living room" receiver. Nothing wrong with that because it's a very good one, but when you stand it beside say a Kenwood R-5000 receiver or even a Realistic base scanner, there is a vast difference in construction.
At the design stage Airnav opted for an SMA connector plus ultra light aerial and also chose not to include an SMA/BNC/PL259 adaptor in the pack. However as there are many using outside aerials and as I haven't heard of problems I assume that the RBs are sufficiently robust.
Quote from flightchecker "following some earlier postings here, AirNav puts it to the customers risk, should a RB suffer from harm when opererated with another (outdoor) antenna, rather than the one supplied with RB itself"
Incidentally, where did you get that from? Not heard it myself before.
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Hard to answer, Dave.
I am runing a "WIMO GP1090" antenna, NOT !!! "DC grounded" as isn't the "postings antenna", BUT its mast connected to the "house earth" by means of an appropriate "earth wire", and the antennas (metallic) foot clamped to the (metallic) mast mentioned. Appears to be a fairly good measure that "catches" / "bleeds" electrostatic buildup at its "point of origin".
If I hadn't the "Wimo" (running since more than two years without any problems so far) my first choice would be the "other antenna" mentioned before. (despite of its lower "gain").
Karl
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Kindly have a look at this thread, bratters
http://www.airnavsystems.com/forum/index.php?topic=977.0
Regards
Karl
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Karl,
We have talked about ESD at length many times, just like in the topic you have posted so we won't go into detail but we will say the following:
Out of the 2000+ RB sold only a handful have come back with ESD damage. That tells you its rare when it happens but yes it can happen. In certain atmospheric conditions the chances of ESD are higher.
We have recommended to those customers that a DC Block is the best way to protect from ESD. So far we have not had any return of RadarBox with ESD damage which has used a DC Block.
Just like any product which connects to an antenna you can choose what antenna you want, but you need to be aware of grounding antennas in certain conditions, not to mention have protection against lightning, a lightning strike doesn't have to be direct hit to cause damage.
Anyhow all of this and more has been said before, please use the search function forum.
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Hello to all and Airnav in particular,
Out of the 2000+ RB sold only a handful have come back with ESD damage. That tells you its rare when it happens but yes it can happen. In certain atmospheric conditions the chances of ESD are higher.
We have recommended to those customers that a DC Block is the best way to protect from ESD. So far we have not had any return of RadarBox with ESD damage which has used a DC Block.
@Airnav
So you still leave it to the customer.
Tell us how someone using an outdoorantenna with a reasonable length of coax can judge whether the setup is
perceptible to statics or not.
The only way is to use a so called DC-Blocker in the first place already.
As a protective measure - always.
Now your recommendation implies that the customer is looking for a suitable external DC-Block,
cutting the precious coax, having both cable ends fitted with extra male plugs to accomodate that little
box with its female counterparts.
Airnav is proudly advertising RB as slim and smallest formfactor around.
Now question at Airnav
Why can you not integrate such a DC-Block inside at the antenna terminal ?
You might as well then proudly advertize the RB with a DC-protected Front End
kind regards
Klaus
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Yachtie45,
Not sure what you mean we leave it to the customer. We have provided you with an indoor antenna with the RadarBox and on our site we have an antenna kit for outdoors. Both with the indoor antenna and the external we have had no ESD failures.
Obviously if you want to purchase any other antenna its best to take precuations such ones which are grounded. High risk conditions of ESD are where there are high winds and heavy rain.
The RB does have limited protection against ESD just like any other device. Adding a DC block would mean there could be loss in senstivity and hence its not worth it considering the rarity of the events and what we provide.
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Just a gentle reminder that the original topic for this thread was for the DPD antenna and not the suscepibility of the RB to ESD. This has been discussed at great length in another thread and topic closed.
I for one would be grateful if this thread could be left to discuss this antenna without having to sift through all this additional material that could be posted in another thread.
spikem
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I for one would be grateful if this thread could be left to discuss this antenna without having to sift through all this additional material that could be posted in another thread.
Agree spikem,
most hopefully looking forward to the "experience reports" prior being announced in this posting.
Karl
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Ok back to the antenna DPD ADS-B Vertical Outdoor Model
in view of the warning "Just like any product which connects to an antenna you can choose what antenna you want, but you need to be aware of grounding antennas in certain conditions"
I am still uncertain whether above mentioned antenna is DC-Ground or not.
Since I developed some scepticism against Front Page Advertisements
I now ask some new owners, has anyone of you probed with a Volt-Ohm-Meter,
at that pigtail cable's end is there any resistance between the inner contact and the outer contact of the connector ?
If the answer is NO ( Zero Ohm) then the ant may be grounded.
Even better check following
Is there any Resistance between the inner contact and baremetal surface of the brackets which will be clamped to the mast ?
If the answer is NO (practically a short) then the antenna is on DC-Ground when fixed to the mast (hopefully grounded in the first place)
Any results appreciated
kind regards
Klaus
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My supllied attenna lead is maked RG-174.
Hi Dud, thanks for that, now I've looked very closely at the cable in daylight, I've found the rather faint RG-174 marking as well.
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I am still uncertain whether above mentioned antenna is DC-Ground or not.
I'll bet it isn't, Klaus ! Apologizes for being THAT pessimistic, "World is bad". :-(
Karl
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Hi All, had my external aerial rigged today, 152 miles range now to the south east and alot more viewed than before.
http://www.ssejim.co.uk/26-sseads1090sj.htm
Having problems with the scanner aerial, no reception at all. Westflex 103 cable same as RB, so think there must be a problem with the Sky Scan DX V1300 Discone Radio Scanner Antenna Aerial. Will try swapping aerials with one we know works first, but that will be next week now. HoHum...
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Hi All, had my external aerial rigged today, 152 miles range now to the south east and alot more viewed than before.
http://www.ssejim.co.uk/26-sseads1090sj.htm
excellent choice, congrets
Karl
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Thanks Karl, 88msg/sec and more flights than I`m used to, a big improvement over the loft set up, I have even turned the network off to concentrate better. Now I can take the laptop out and about and see what its like high up on Exmoor, when the snow clears. Just need to get the scanner aerial sorted.
Cheers All, Dave.
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Thanks Karl, 88msg/sec and more flights than I`m used to, a big improvement over the loft set up, I have even turned the network off to concentrate better. Now I can take the laptop out and about and see what its like high up on Exmoor, when the snow clears. Just need to get the scanner aerial sorted.
Cheers All, Dave.
Are you seeing traffic at lower flight levels than before?
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Hi Dave,
just in case, should your scanner antenna have given up, there is a good alternative:
http://www.sirioantenne.it/prodotti_ant.php?idc=1011280996&idg=1008171225&idp=104
Outstanding in terms of its mechanical machining and its electrical specifications. I'm already running it for quite a long time , both Scanner- and Virtual Radar- application. Very happy with it, even "looking good" :-)
On the other hand, I don't think your antenna itself has given up. "Just mechanics". Looks like its due to a connector, that the coax lost contact with. Most hopefully not to be the coax itself suffering "waterpenetration".
Regards
Karl
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Hi, it`s a new item haven`t had time to check if the aerial is a dud yet.
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HI Guys
A quick update on the antenna. Overnight I had an email from Dave at dpdproductions. He advised me mine is enroute. He has given me details to be able to track the package so I'll give an update on it's arrival.
John
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Well, SDB antenna arrived this morning ( After VAT man had his £12 Cut) , all well packaged and undamaged.
I have taken a few photos for thoses that are interested to show the genaral quality of the manufacture. Let me first apologize for the focus being a bit out as I haven't quite mastered macro on this new camera but you can see that the antenna is totally enclosed in a waterproof grey plastic tube and sealed at both ends and has a pigtail fitted to an N connector.
It comes with a 4 page instruction sheet and 2 plastic covered jubilee clips along with a few cable ties.
As the weather was quite favourable I decided to venture onto the roof and get the job done before the wife had time to lecture me about my age etc and managed to complete the job without any problems. 10 metres westlake 103 and a sma/N plug pigtail at the radarbox end were used to save stressing the connectors. Disregard the thin cable to the side of the antenna photo on the roof as it is a guy for hoisting a HF Wire.
As for performance, I can only say that after a few hours use I am well impressed with the outcome. My home location is not far from Liverpool and just above sea level. I was originally using the supplied antenna in the loft and getting around an 80 Mile radius with a large gap over Wales. This has now improved to a 165-175 in an almost circular pattern. Of course the extra 6ft or so in height has made a difference but it seems to be performing as it should and for my use is more than adeqate.
I was hoping to show a before and after screenshot but for some reason cannot access the screenshots folder for the previous shots. I am on Vista and can save a Shot to the screenshot folder and see my previous ones but cannot see it through My Computer or file>screenshot>explore. I have looked in the recycle bin and still no sign ...any ideas anyone? Anyhow I have just managed to get one of the SDB range to give you an idea.
Spikem
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More Pics
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Screenshot
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Can you tell me if you are seeing more lower level traffic now at your local airport? what sort of level can you see down to?
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Hi Spikem glad to see the aerial has arrived and what appears to be an improvement in coverage. I'd like to see your comparison shots. Mine is due anyday now also.Can you please confirm the cable and connections you are using and where might i get them. i am in Northern ireland and not sure a local source exists.I was promised some assistance on this, not from the site i hasten to add, but it never materialised.
Regards
John
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Hi Spikem
where you buy your antenna?
Can you give-me the website?
Thx.
Best regards.
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Hi John
Cable is W103 from here http://whwestlake.110mb.com/ Tel: +44 (0)1409-253758 Mobile: 07774 635077.
I gave him a call on the Friday and it was in the post Monday. I also asked him if he could make up the sma to N plug adapter cable for the Navbox and he said he had them already made up in preset lengths. Very nice chap to deal with and also very helpful.
Low level traffic has increased somewhat. I can now track them at Liverpool and Manchester down to 350 feet or so as opposed to around 800-900 previously. I wouldn't expect to get them any lower than that from my location which is about 20 miles from each and also having a large flyover around antenna height just to the side of me.
Regards
Martin
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Hi Miguel
http://www.dpdproductions.com/page_vhf_air.html . He will answer all your questions by return email if you have any.
Regards
Martin
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Before and after pics as requested.
Sorry for the poor quality on the loft pic , I had to scan it from a picture I made as I am still unable to access the screenshot folder for some reason.
Martin
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Before and after pics as requested.
Sorry for the poor quality on the loft pic , I had to scan it from a picture I made as I am still unable to access the screenshot folder for some reason.
Martin
Freeow!
4 people with coverage like that would cover the whole UK at medium to high level!
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HI Martin
Thanks for the cable info I'll make the call tomorrow as my aerial is due shortly. The increase looks encouraging already so i can't wait to give it a try. Thanks again for the help.
Regards
John
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HI Martin
As you know I also ordered the ADSB antenna from DPDproductions the order was placed on 27th January. Via the tracking receipt given to me I have been advised the following 'Your item left the United States from ISC LOS ANGELES CA (USPS) at 10:00 PM on February 10, 2009'.
I was just wondering how long it took to arrive with you? I will contact Dave also for an update. Had it been here today I had a person on standby to erect it so it is a little frustrating that it hasn't yet appeared.
John
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Hi John
The same thing happened to me. You will find that the messege will not change. The next thing to arrive will be a letter from the parcel service stating that it is waiting for you to make a payment for VAT before they can release it.
The fact that it is logged with the tracking service indicates that it is on its way.
Just hang on in there for a little longer I would guess.
Martin
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Hy John, In the same boat here with my order, according to tracking my order arrived in this country last tuesday, so I did some further tracking to be told that they tried to deliver friday but failed, so now hope it arrives tomorrow ( Monday) I guess I just have to be a little patient. Cant find out who the carriers are so that does not help.
Cheers Peteeds. 2W1 FJZ
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Thanks Guys I'm learning to become more patient. I spoke to Dave and he confirmed the more or less what you are saying. he has 5 items altogether issued around the same day into GB and none have yet reached their final destination.
John
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Parcellforce letter arrived this morning seeking payment of VAT which I paid via their website. Package due with me tomorrow so further updates to follow.
John
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Same here John, paid on line, delivery tomorrow, Just hope for some calm weather for next couple of days so I can get up on the roof to fit it. Keep you posted when up & running.
Cheers Peteeds. 2W1 FJZ.
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HI All it's here, my DPDproductions antenna is here!! It just arrived via parcelforce which is interesting. They sent me an email this morning stating they understand the inconvenience and frustration of the delay in me receiving the package. Their records allow them to confirm to me that the package has not yet been received in the UK. When I checked on Monday on their site it told me it arrived into LHR on 12th Feb at 16.10pm. It then arrived into the Belfast Depot on 20 February. I got a letter on the 24th asking for VAT payment , paid it online with Parcelforce and was guranteed delivery today. So despite all the odds it made it. Parcelforce don't know where it is and have offered me forms for compensation if the sender raises an inquiry.
Anyhow I now have a delay to have it installed as the guy doing it for me is unavailable for 10 days and I don't do ladders. Further updates to follow, now what will I buy with the compensation!!!!!!!!!!!!!!!!!!!!!!!!!!
John
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Glad to hear it has arrived john. You could probably give it a try on a pole in the meantime whist you are waiting. I would imagine that you are in a good position to catch the atlantic traffic from where you are. Keep us posted on your progress.
MArtin
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HI Martin
Might try it out as a just to see. My cable is due in the next I am in a good spot indeed for the Transatlantic stuff. I am hoping that it might allow me to get out towards the West Coast of England and down to Dublin. Anything beyond this and I'll really be a happy bunny.
John
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Hi all,
as a technical newbie, can someone please tell me if i buy this antenna do i need to be worried about killing my radarbox if i dont put a dc block in line? i would like an external antenna but not if there is a chance of tears before bedtime, especially as i had to save long and hard for it.
thanks
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Hi all,
as a technical newbie, can someone please tell me if i buy this antenna do i need to be worried about killing my radarbox if i dont put a dc block in line? i would like an external antenna but not if there is a chance of tears before bedtime, especially as i had to save long and hard for it.
thanks
A DC block is not necessarily going to help a lot, perhaps a better approach would be to use something like a 1dB attenuator (from MiniCircuits for instance) as this would discharge any static build up whereas a DC block is essentially a capacitor and is not designed for large DC voltages, it could flash over internally creating exactly the sort of current spike that can cause problems.
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Any updated info regarding the antennas ?
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Mine is working a treat, No problems. A few others are just in the process of installing them I believe.
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Mine should be up this weekend weather permitting. The frustrating part was getting the mounting pole for it. This is, thankfully, now sorted so roll on Saturday/Sunday.
John
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Hi Guys, My DPD is up & running, early indications are looking good,My old system was a BS External ant on a 40 ft mast, Elad Masthead amp, westflex coax with a Jim M75 internal amp at the box at an outlay of nearly £600 .00. \the DPD is doing as well if not better & is completely unassisted. It seems to be very much more sensitive on receive. I am just giving it a few days to build up the polar diagram but getting sigs where I got nothing before. Looking promising.
Cheers Peteeds 2W1 FJZ.
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I am considering an external antenna so i awaits "user reports".
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I am considering an external antenna so i awaits "user reports".
Hello,
I would also like to hear more feedback from those who have installed this antenna.
It would be interesting to hear from those who have gone from using the stock RB antenna to the DPD antenna. The best comparison would be if someone used the DPD antenna in a location that was the same or very close to the location of the original with a similar length cable run, even if it was just temporarily to compare the approximate performance difference of the two.
If you went from using the RB antenna indoors next to a window to mounting the DPD on top of the house then any comparison comments are not going to help much, but anything would be appreciated even if your new antenna did go straight to the roof.
Thanks
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HI Falcon I'm up for that as my DPD was to be fitted last weekend. Due to a 90th Birthday party (no not mine) and the fitter being "on duty" it didn't happen. I'll change it tonight around midnight and let it run for 24 hours at the window where the supplied aerial presently sits. I'll fit the flylead only into the radarbox for a similar length cable run. It'll be interesting to see what happens and at least the DPD will get usage of some kind.
John
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HI Falcon I'm up for that as my DPD was to be fitted last weekend. Due to a 90th Birthday party (no not mine) and the fitter being "on duty" it didn't happen. I'll change it tonight around midnight and let it run for 24 hours at the window where the supplied aerial presently sits. I'll fit the flylead only into the radarbox for a similar length cable run. It'll be interesting to see what happens and at least the DPD will get usage of some kind.
John
Hi John,
Excellent. I await your feedback.
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I bought one of these antennas to see how well it works compared to the stock antenna. I didn't get any change in contacts. Since I don't really get many contacts because there really are so few anyway, the antenna doesn't really extend my range. Note: I get more mode-s, then ADS-B.
The advantage of this antenna though, is its grounded design. I live in tornado alley and that means we get a lot of lightning (we are having an electrical storm as I type, and all my antennas are disconnected from the radios). Not only do antenna's need grounding and have fuses in-line, you need lightning rods to attract lightning away from your antennas.
So, as with most things, curiousity compelled me to disassemble it. I pulled the two plugs (top and bottom, and pushed the antenna out the bottom to take a look.
First impression is very good. The whole antenna is placed in a schedule 80 PVC pipe (overkill, as a schedule 40 would be good enough). This PVC pipe will not flex. Then the antenna elements are covered in a thick shrink-wrap to keep out moisture/condensation and add to the rigidity. Without taking the shrink-wrap off I can see that this is a 10 (1/2-wave) element collinear, with a 1/4 wave stub at the top and at the base.
The construction is top-notch. I decided to not let my curiousity cause me to remove the shrink-wrap, as I can feel under it, that they seem to use a rod to make the length rigid, and place the mini-coax soldered elements against the rod. I don't know what the rod is made out of (obviously not a conductor), but it seems pretty firm.
This is a quality made antenna.
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Hi OKC-Steve
First of all, thanks a lot for sharing all this information.
This kind of antenna (ten dipoles) has more than 6 Dbs gain and will work very fine.
But You always need to have clear horizon, if possible 360 degrees.
About ligting, bolts ... I can say that I have 2 antennas just like ..
One with 21 dipoles (grounded) and one with 8 dipoles (not grounded)
I never disconnect the cables from RBs, even when hard ligtening, bolts and so on, for two years and never had some problems neither in SBS nor RB.
Both antnnae are at 16nth floor, so very exposed to discharges...
Maybe that some people got problems with RBs due to low moisture area...
This can produce EDS at connecting the cable to the RB and damage it.
Well, theese are my own experience ...
Best Regards. Juan
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Hi OKC-Steve
I was suprised that the antenna did not extend your range compared to the stock antenna. One thing that was mentioned when I contacted Dave at DPD productions was to ensure that no more than the lower 7 inches of the antenna are connected to the mast, as any more has a limiting affect on it's performance. You are probably aware of this already but the info is handy for other users
.
Regards
Spikem
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I thought the antenna might help me see some of the stuff south of me, coming out of DFW airport. Alas, the town here is actually in a very large valley, and you don't notice it until you drive about 10 miles south and then you can see the whole valley below. It's this ridge that kind of blocks me.
I think I'm seeing more mode-s hits though. Just not a lot of ads-b around here. After about midnight I don't receive anything at all. I think they even roll up the sidewalks...
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It's up it's up. Finally the aerial was mounted on the roof this evening. Initial thoughts?
WOW WOW WOW!!!!!!!
I have attached a screen shot of the polar diagram running for approx 2 hourss. I have had Tornados a first for me and well the polar diagram says it all. The aerial is on a 6ft pole on the chimney stack.
I can't wait for a full day of traffic. My flights would normally be showing around 10 maybe 14 aircraft on a good night late evening .This evening after it was erected I was in the 50+ mark.
Regards
John
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It's up it's up. Finally the aerial was mounted on the roof this evening. Initial thoughts?
WOW WOW WOW!!!!!!!
I have attached a screen shot of the polar diagram running for approx 2 hourss. I have had Tornados a first for me and well the polar diagram says it all. The aerial is on a 6ft pole on the chimney stack.
I can't wait for a full day of traffic. My flights would normally be showing around 10 maybe 14 aircraft on a good night late evening .This evening after it was erected I was in the 50+ mark.
Regards
John
Hi John,
Do you need any help in keeping yourself on the ground? A 400 - 500 percent improvement would get me jumping. Look forward to seeing the full day polar.
Regards,
Darryl
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Hi Darrl boy has this hobby really taken off now (no pun intended). I run the RB overnight almost every night. With the supplied antenna mounted indoors at 8am I would normally have about 140 aircraft recorded. This morning the first for the DPD outside, I had 320 at 8am. Happy? No euphoric!!!!!!!!!!!!!!!!!
John
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Hi John
Congrats mate on getting it up and running. I had an idea you wouldn't be dissapointed. Give us a look at your polar plot to see the improvement.
Martin
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HI Martin thrilled with it, what a change. I missed attaching the polar diagram last night dohh!!! In work now but I'll post it later this evening.
John
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Hi all as discussed here is the polar diagram for the DPD aerial mounted externally. This is it after its first 24 hours.
I'm thrilled with the increase in contacts. it has already got me a range of aircraft types and Airlines which I had not logged before.
Maybe it's just me but does the polar diagram not look a bit like a map of Northern Ireland?
John
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Hi All
Here is another happy customer of DPD antennas.
Attached is my polar diagram centered at Wakefield West Yorkshire.
The antenna is mounted on a pole one meter above my roof ridge line.
The antenna has given me an overall improvement of about 45%.
The polar diagram was taken after 24Hrs of the antenna being installed and running.
Cheers for now.....Ralph
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hi.
can you please tell me de name of the antena, i just got my airnav 2009 box and will be sending data from jfk, la guardia and erw 3 big airports in my area.
hava a good day.
hamerhead
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Hi Darrl boy has this hobby really taken off now (no pun intended). I run the RB overnight almost every night. With the supplied antenna mounted indoors at 8am I would normally have about 140 aircraft recorded. This morning the first for the DPD outside, I had 320 at 8am. Happy? No euphoric!!!!!!!!!!!!!!!!!
Hi John,
I purchased the DPD and have had it running on the roof for a couple of months with a 100' of LMR400 with no amp and am seeing excellent results for my area. The areas that aren't blocked by hills I am getting 200+ nm with aircraft at cruising altitude and all the way down to 200-300' at an airport 20nm away and about 2000-3000' at 34nm away and that's with the signal going between the gaps in the hills in my area.
It's good to hear you are also happy with your antenna. I didn't see your reply until today.
Regards,
Darryl
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hamerhead,
Here is the link to the antenna.
ADS-B Vertical Outdoor Model Antenna
http://www.dpdproductions.com/page_vhf_air.html
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Hi Darryl, are you in the UK, if so who supplied the LMR400, and how much does it cost please?
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Hi Darryl, are you in the UK, if so who supplied the LMR400, and how much does it cost please?
Hi,
I purchased it from these guy here http://www.infinitecables.com/antenna_cable-nm-nf.html I purchased 100' of LMR400, and a 3' pigtail of LMR195 to go from the LMR400 to the RB with the connectors on them. I'm not in the UK. I was concerned about the total length and signal loss but from what I had read about the DPD antenna and the LMR400, I thought I may have a chance of making it work without an amp, and it turns out I was right, at least for my installation. I may pickup more aircraft or hold onto aircraft for a longer period of time with a mast head pre-amp, but at this point with the results I am getting I don't feel compelled to fork out the extra cash.
Regards,
Darryl
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Hi Darryl, many thanks for the link, I was hoping for a UK source, but c'est la vie!
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Hi Darryl, many thanks for the link, I was hoping for a UK source, but c'est la vie!
If you are merely trying to find a UK source of LM 400, this company came up on an internet search.
http://www.wirelesspro.co.uk/department/bulk_cable/ (http://www.wirelesspro.co.uk/department/bulk_cable/)
I have no idea whether they are good, bad or indifferent, or indeed their price is good or bad.