Hi,
Is anyone using a SSB SP-7000 preamp and an Icom 910H powered via direct feed from the coax. I am not able to turn the preamp on with this method, I set the menu for the preamp and the front panel; it recognizes a preamp but it's not working, any ideas?
73 Peter WB2OQQ
Not sure what you mean by "recognized a preamp" (I don't have a 910), but if you have a lightning arrestor in between the rig and the preamp, they usually block DC from passing. Mine does, so I had to power it with an external cable (which, now that I think of it, kind of defeats the purpose of the lightning arrestor...!).
Greg KO6TH
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Date: Mon, 11 Aug 2008 16:39:56 -0400 From: roi@optonline.net To: AMSAT-BB@amsat.org Subject: [amsat-bb] SSB Preamp
Hi,
Is anyone using a SSB SP-7000 preamp and an Icom 910H powered via direct feed from the coax. I am not able to turn the preamp on with this method, I set the menu for the preamp and the front panel; it recognizes a preamp but it's not working, any ideas?
73 Peter WB2OQQ
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
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Also, most TX amplifiers have a series capacitor on the input, which will also block the DC power. With the TX amp switched off/out, there is usually a DC path, but check the schematic.
Alan WA4SCA
Not sure what you mean by "recognized a preamp" (I don't have a 910), but if you have a lightning arrestor in between the rig and the preamp, they usually block DC from passing. Mine does, so I had to power it with an external cable (which, now that I think of it, kind of defeats the purpose of the lightning arrestor...!).
Greg KO6TH
----------------------------------------
Date: Mon, 11 Aug 2008 16:39:56 -0400 From: roi@optonline.net To: AMSAT-BB@amsat.org Subject: [amsat-bb] SSB Preamp
Hi,
Is anyone using a SSB SP-7000 preamp and an Icom 910H powered via direct feed from the coax. I am not able to turn the preamp on with this method,
I
set the menu for the preamp and the front panel; it recognizes a preamp
but
it's not working, any ideas?
73 Peter WB2OQQ
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
_________________________________________________________________ Your PC, mobile phone, and online services work together like never before. http://clk.atdmt.com/MRT/go/108587394/direct/01/ _______________________________________________ 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
Hi Peter,
Does it show PAMP on the display or does it come on for only very shortly? I have this setup working at the Delfi-C3 groundstation without problems with a lightning arrestor in the circuit (gas discharge type) If you have a short somewhere in the cable the PAMP sign will only light very shortly and will be off again due to the protection inside the IC-910. You could also carefully check the setup with a bias tee if you have one available. Should you have access to the preamp right now (ie, its not already outside and hard to reach) you could try with a short cable and listen if the relay comes up (no voltage on the coax means pre-amp bypassed = relay off) If I understand correctly you have enabled the pre-amp in the menu? (Press MENU long, go to 435 PRE with up and down keys and make sure it says ON) If you have a TX PA, then most probably it has an input capacitor as Alan already pointed out. Try without the PA in the loop.
Good luck and 73's
Wouter Weggelaar PA3WEG
On Tue, Aug 12, 2008 at 1:29 PM, Alan P. Biddle APBIDDLE@united.net wrote:
Also, most TX amplifiers have a series capacitor on the input, which will also block the DC power. With the TX amp switched off/out, there is usually a DC path, but check the schematic.
Alan WA4SCA
Not sure what you mean by "recognized a preamp" (I don't have a 910), but if you have a lightning arrestor in between the rig and the preamp, they usually block DC from passing. Mine does, so I had to power it with an external cable (which, now that I think of it, kind of defeats the purpose of the lightning arrestor...!).
Greg KO6TH
Date: Mon, 11 Aug 2008 16:39:56 -0400 From: roi@optonline.net To: AMSAT-BB@amsat.org Subject: [amsat-bb] SSB Preamp
Hi,
Is anyone using a SSB SP-7000 preamp and an Icom 910H powered via direct feed from the coax. I am not able to turn the preamp on with this method,
I
set the menu for the preamp and the front panel; it recognizes a preamp
but
it's not working, any ideas?
73 Peter WB2OQQ
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
Your PC, mobile phone, and online services work together like never before. http://clk.atdmt.com/MRT/go/108587394/direct/01/ _______________________________________________ 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
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
participants (4)
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Alan P. Biddle
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Greg D.
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Peter
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wouter weggelaar