Bob,with the AG25 preamp on I see s5/6. I do get the audio at a higher level ,it seems to me,. Just added to AO-51 the L/u to my doppler for satpac32 FM/FM to add for cross mode do I have to add a separate line or add to the info on the FM/FM string. If anyone can figure out what my ? is pls let me know what has to be done. ThanksJack WA1ZDV
At 11:45 AM 3/16/2010, Jack Barbera wrote:
Bob,with the AG25 preamp on I see s5/6. I do get the audio at a higher level ,it seems to me,. Just added to AO-51 the L/u to my doppler for satpac32 FM/FM to add for cross mode do I have to add a separate line or add to the info on the FM/FM string. If anyone can figure out what my ? is pls let me know what has to be done. ThanksJack WA1ZDV _______________________________________________ Sent via AMSAT-BB@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
Jack,
Sorry if this was covered, but do you have an internal preamp in the radio? If you do, turn it off. Even if there is not one, maybe you have an attenuator on the input ( a lot of the newer radios do nowdays). Try turning on the attenuator (probably 10dB) and see if that sounds better. If you have SSB see what S-meter rise you see in SSB. My preamps push my S-meter in FM a lot higher than when in SSB (typ S-5 vs S-2/3). I am running a 22-sB gain 432 preamp on my new Lindy antenna into a FT-847. The NF is probably approx 0.5 dB (Mgf-1302).
The others gave you methods for testing it with local signals (measure S-meter rise on/off with a local rptr; compare S-meter with preamp connected with just the radio connected; moving antenna so that a local signal becomes near noise level and see if preamp pulls it up out of the noise (by ear)). Usually a rise in background noise is the sign of a healthy preamp - but not always. If signals are heard better without the preamp, then it probably is "broken" (always check dc power connections in this case). the AG25 is probably powered thru the coax by your radio (check that the radio is putting out voltage on the center pin). Since you are seeing noise rise these latter ideas are applicable (just covering the field for others that may be having preamp problems).
GL
73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com 500-KHz/CW, 144-MHz EME, 1296-MHz EME DUBUS Magazine USA Rep dubususa@hotmail.com ======================================
On 16 Mar 2010 at 12:45, Jack Barbera wrote:
Date sent: Tue, 16 Mar 2010 12:45:13 -0700 (PDT) From: Jack Barbera barberaalderwood@yahoo.com Subject: [amsat-bb] (no subject) To: Amsat Reflector amsat-bb@amsat.org
Bob,with the AG25 preamp on I see s5/6. I do get the audio at a higher level ,it seems to me,. Just added to AO-51 the L/u to my doppler for satpac32 FM/FM to add for cross mode do I have to add a separate line or add to the info on the FM/FM string. If anyone can figure out what my ? is pls let me know what has to be done. ThanksJack WA1ZDV
I also have both Icom AG preamps U and V After blowing two in 3 months i finally ended up with the AG and they are still working after 2 years now. As someone suggest it will be nice to have some figures to be able to have an idea of their performance.
I don't know how the others react but on my FT-847 i got an increased of 5 DB on the noise when i switched it on on VHF and nearly no signal increased on UHF but the amplification is there as when i got no signal at AOS without it and a S-1 to S-2 with the preamp is ON.?
Without the presence of a signal on UHF i cannot tell if the preamp is on or off just by looking at the meter and even when listening the noise i cannot tell if the preamp is switched on?
"-"
Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe DSTAR urcall VE2DWE WAC BASIC CW PHONE SATELLITE
participants (3)
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Edward Cole -
Jack Barbera -
Luc Leblanc