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Author Topic: Pre amp location - does it not give benefit if it is not next to aerial?  (Read 13527 times)

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stevebarker12

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I have installed a proper aerial on my roof (via airbandonline) and it gives good reception for my RB.
It was put up by an installation company and the 10m cable lead down into an upstairs  room where my PC & RB are located
I have read that a pre-amp may make it even better - but I don't want to
either go up and install a pre-amp next to the aerial (don't fancy the climb!) or get someone to do it.
My question: is it a waste of time to purchase & install a preamp next to my PC/RB
in my upstairs room? ie is a pre-amp only of benefit if located right next to the aerial
.
Advice appreciated
Kind Regards
Steve

WAL 2T

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Hi Steve,

You would only be amplifying any loss induced noise at the receiver end of the feeder so an amplifier would be of limited use in this case. If it made any difference at all I would expect it to be minimal.

hth
Chris
Chris

Under the EGGP 27 Centreline & 15nm from EGCC

imropes

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Hi steve. I agree with Chris. You state you have good range so i would leave things as they are. How is your polar diagram range? As a ham (G6XHK) i will not use them in my radio work.Not impressed with the hype. Discussion please.

carp777

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Hi Steve
               thinking of getting an proper aerial myself got the radarbox from ABOL  so thinking of going back for aerial . Can you give me an idea of price and price for installing as i dont fancy going on roof myself (chicken) thanks
                                         
                            Bryn

stevebarker12

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Thanks to Chris & ''imropes'' - yes, i suspected as much.
Bryn:
I purchased from airbandonline a 10m cable and an aerial-see attached link
http://www.airbandonline.co.uk/kapl_sbs1_aerial.htm
ie a A HBA-1090 Home Base Aerial
Overall cost ca £110 -not cheap but it made a big difference to my range.
Good advice from airbandonline given.
Installation - I had a normal TV aerial + RB aerial + Airband scanner aerials all installed at same time (3 in total).I bought cable/aerials/stub masts -but not fixings/brackets.
This cost £130 - a rip off if ever there was one. Took them just over 1 hour max.
I live in Preston and towards the top of a hill - but not on top and I have very close tree/houses (we live in a semi).Height & proximity to other obstructions is the main thing
If you go ahead make sure they put the RB aerial separated from other aerials and as high as possible. It would be better if you bought fixings (bracket/aerial cable) yourself like I did -any extra brackets/cable they charge over the odds for (labour really) but its difficult knowing what fixings they need.
Hope this helps
Steve

carp777

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Thanks for that Steve i also am in Preston  Ribbleton Blackpool Road area so not so far away from you

Thanks again for info

                                     Bryn

stevebarker12

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Just a quick follow-up on my question which may be useful to someone - for £40 i decided to buy a preamp and put it  next to my RB/PC (my aerial is on roof).
Not expecting it to do much I am quite shocked to find it made a big difference -lots more contacts
What shocked me more was that twiddling with the rb/aerial connectors made a vast difference as well. I read on another post that the internal wire connections to rb can make a big difference - screwing/tightening the nut on the rb makes a big difference as does other aerial/connector contacts.But don't overtighten!
My advice would be to tweak your screw connectors to optimise reception
Steve
Preston
UK

daveg4otu

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What shocked me more was that twiddling with the rb/aerial connectors made a vast difference as well. I read on another post that the internal wire connections to rb can make a big difference - screwing/tightening the nut on the rb makes a big difference as does other aerial/connector contacts

If this is the case  then IMO you either have poorly fitted  plugs/sockets/connectors on your cables....or a dodgy  ant socket on the box .
5 Miles N of BHD at 50.28.28 N/3.30.43W...400ft amsl.

Hampshire, Devon, Dorset and Isle of Wight  Airfields Websites.....
http://devonairfields.tripod.com/index.htm

stevebarker12

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Yes I'll check this out
Steve

CoastGuardJon

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  • Mullion Cove, Kernow --- sw Cornwall UK.
Hi Steve, as Dave says above this does sound like a dirty or poor connection, but please keep us posted as to what you find, by going back to standard twig only and then with pre-amp - to my mind there is no logical explanation, the pre-amp at the back of the box although boosting desired signal, will subtract its own loss.    What amp did you buy - at that price, unless s/h, isn't going to have the very tight filters requires to take out the out of band crap and noise and just retain the 1090 signals.
ANRB :  AOR AR8000 : Icom R-7000 : Icom IC-R9000 : JRC NRD-545 : OptoElectronics Digital Scout and OptoLinx Interface; Realistic Pro-2005 : UBC 800XLT - listed in alphabetical order, not cost, preference, performance or entertainment value!

stevebarker12

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After experimentation I have concluded the pre-amp next to the RB/PC does not give
improvement. (**). However, I have stopped further experimentation because I don't want to keep connecting/disconnecting the RB leads.
I suspect the pre amp to RB connectors should not have undue stress put on them by keep disconnecting them. The connections are very sensitive making a big difference to reception - the preamp -rb -connector leads needed to be completley horizontal.
I used a Watson WRP-1300 (25-1300MHz) Pre amp from CPC products Preston which cost £40
** When i connected this preamp to an airband hand held scanner - right next to the scanner in between the radio and small aerial - it DID improve reception - ATC can be heard better (bit more more noise across the scan range which can be removed) so i will be keeping this connected up
Looks like a pre-amp next to the aerial is the only option. I'd recommend to anyone that if they put an aerial up then go the whole hog and pre-amp it as well while your at it
Kind Regards
Steve
Preston

Bethsalem

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Any recommedations for radio scanner pre-amps in the sub £60 price range? I was thinking specifically of the Moonraker MRP-2000 MK2 wide band pre-amplifier.  Does anyone know if it's worth buying?

radarspotter10

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Any recommedations for radio scanner pre-amps in the sub £60 price range? I was thinking specifically of the Moonraker MRP-2000 MK2 wide band pre-amplifier.  Does anyone know if it's worth buying?

hi Bethsalem
In my home town a preamp is useless on the air band owing to it being am signal, FM around say 145 mhz to 560 mhz was OK using the preamp, now that's just my home town yours will be different.
all the best pat

FlyOverMe

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A preamp should always be just below a stub at the antenna! Otherwise you amplify the loss on the cable. The masthead is where the amp should be. Period!!!!

gzerovti

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I have the Elad preamp and it is installed inside the loft midway between the RB and my Radar Extender antenna. It is nice and dry in the loft.

The difference it makes is phenomenal! I live near Leeds at 150 mtrs asl but I am in a bungalow surrounded by houses but with the preamp on I can see aircraft in myFlights across into Belgium, Holland, right down to the south coast of England and up as far as Aberdeen. NI OK but Eire not very good. Without the preamp at least 50% reduction.

I once tried the preamp right next to the RB with quite good results as well.

Terry
G0VTI - On the flight path to EGNM