[amsat-bb] Re: Icom AG-35 Preamp Question

[Mike Seguin N1JEZ]

Sorry guys, thought you were talking AG1200, not AG35....

73,
Mike, N1JEZ
AMSAT 29649
"A closed mouth gathers no feet"

----- Original Message ----- 
From: "Mike Seguin N1JEZ" <n1jez at burlingtontelecom.net>
To: <kc6uqh at cox.net>; "'Lawn, Richard'" <RLawn at uarts.edu>; 
<amsat-bb at amsat.org>; "Mark L. Hammond" <marklhammond at gmail.com>
Sent: Sunday, August 12, 2012 8:57 AM
Subject: [amsat-bb] Re: Icom AG-35 Preamp Question


> Hi Mark,
>
> That is the way they're supposed to work. +12v receive - 0v on xmit.
>
> It is fine with a Yaesu FT-736R using the built in preamp feed system - 
> power up the coax. Just have to watch out for any DC block.
>
> It also would work with a Yeasu FT-847 if it had 1296.....
>
> I had one for a while. I found I had to open it up and retune as it was 
> set for the low end of the 23cm band?!? My biggest problem was that it was 
> only good for about 15 watts. I had to use it after my DL2AM 80 watt 
> amp....
>
> Mike
>
>
> ----- Original Message ----- 
> From: "Mark L. Hammond" <marklhammond at gmail.com>
> Subject: [amsat-bb] Re: Icom AG-35 Preamp Question
>
>
>> Hi All,
>>
>> Somebody please clarify---I may be wrong, but I thought the Icom preamps 
>> did the following with Icom radios:
>>
>> In receive, 12V is powered up the coax.  Device is powered, preamp is ON.
>> In transmit, the 12 power feed is stopped. Device is not powered, and 
>> it's bypassed during xmit.
>>
>> If this is the case, it complicates greatly the use of Icom preamps on 
>> non-Icom radios (means there isn't a typical RF-sensed bypass circuit, 
>> which means it would be easy to blow in a non-Icom radio).
>>
>> Am I remembering this wrong?
>>
>> Mark N8MH
>>
>> At 09:30 PM 8/11/2012 -0700, Art McBride wrote:
>>>Rick,
>>>I suggest you use a VOM or DMM to measure the current drawn on 12 volts
>>>going to the power injector. If everything is connected correctly It will
>>>draw 30-200 mA. Confirm that you have continuity in your coax. Some
>>>lightning arrestors have a DC block built in. It is best to test it with 
>>>a
>>>short run of coax between the preamp and the power injector at the radio
>>>while listening to a local repeater to see if the signal increases when 
>>>you
>>>apply power to it. If it operates then you can proceed to determine if 
>>>there
>>>are problems with the coax to the antenna, not carrying the 12 VDC.
>>>73
>>>Art,
>>>KC6UQH
>>>
>>>-----Original Message-----
>>>From: amsat-bb-bounces at amsat.org [mailto:amsat-bb-bounces at amsat.org] On
>>>Behalf Of Lawn, Richard
>>>Sent: Saturday, August 11, 2012 3:30 PM
>>>To: amsat-bb at amsat.org
>>>Subject: [amsat-bb] Icom AG-35 Preamp Question
>>>
>>>I bought an Icom AG-35 preamp about a year ago. The fellow ham advertised 
>>>it
>>>as virtually brand new and it was/is. I planned to use it this summer 
>>>with a
>>>TS-2000 which doesn't supply 12v voltage to the coax to power a preamp as
>>>other xcvrs do. I used a Mirage KP2 unit to inject power to the coax to
>>>drive mast mounted the preamp. When I turn the power on there seems to be
>>>little or no noticeable difference in background noise and worse than 
>>>that I
>>>cannot here any signals on FO-29 downlink, and I know the bird has been
>>>active. Any suggestions? Is the preamp fried? I can't even get the 
>>>weather
>>>proof case off to trouble shoot, not that I'd know what to look for. Any
>>>suggestions on repair?
>>>
>>>TNX
>>>73
>>>Rick
>>>W2JAZ
>>>
>>>
>>>_______________________________________________
>>>Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
>>>Not an AMSAT-NA member? Join now to support the amateur satellite 
>>>program!
>>>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>>>
>>>_______________________________________________
>>>Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
>>>Not an AMSAT-NA member? Join now to support the amateur satellite 
>>>program!
>>>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>>
>> _______________________________________________
>> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
>> Not an AMSAT-NA member? Join now to support the amateur satellite 
>> program!
>> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>>
>
>
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>