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307 Amps 2X6 Base Amp Issue

you said the amp was new, but mentioned the previous owner.
did you mean that it was new to you?

also, a 5 watt deadkey is too much for the two pill section of that amp.
try it with a 2 watt deadkey and see if that improves anything.
LC
My friend bought it in July, then won another 2x6 and he gave it to me. So it's a couple months old. I'll try that and see if it helps. Thanks!
 
No improvement at all using a 2 watt dead key. On SSB it's about 15W PEP, no carrier on SSB. This amp sounds great on AM, no issues with it at all.
 
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No improvement at all using a 2 watt dead key. On SSB it's about 15W PEP, no carrier on SSB. This amp sounds great on AM, no issues with it at all.
SSB should never have a carrier, it’s all modulated wattage. Since it sounds great on AM either just run it on AM or like you said, send it back to be biased forSSB use. Great looking amp board and work. Interesting how he crammed those power supply’s in there, not sure what to think about that.
 
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SSB should never have a carrier, it’s all modulated wattage. Since it sounds great on AM either just run it on AM or like you said, send it back to be biased forSSB use. Great looking amp board and work. Interesting how he crammed those power supply’s in there, not sure what to think about that.
It's a really nice amp, I love it. Will be even better, once I get it sounding good on SSB.
 
Straight answer #1. The amp is biased for SSB. This is obvious by each 2 pill section having that large sandbar resistor on top of the input transformers.
The SSB delay capacitor can be seen behind the smaller relay.

This switch you mention sounds like it can turn the bias on/off. With no bias on SSB the relays chatter.

I don't know for sure but.... 307 builds amps that can turn on and off the 2 pill section so with that said.... Somewhere on that box or you buddys receipt should have a build number or some kind of details.
What does the front look like?

Very nice looking built amp BTW.
 
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This is what it looks like on the outside. I was told that it was not biased, nor does it have a SSB delay. So I guess I'll have to see if he has the paperwork for it.
 

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your gonna hate me but can you take a picture of the switches from inside the amp?
Sure, next time I take the cover off. Might do that tomorrow. I noticed that I have an AC hum coming from my power supply powering the radio, and can hear it in my carrier on AM. I'm beginning to suspect that as the root cause of my audio problem. I just ordered another one and will know for sure after I hook up the new one.
 
Looks like they use the small relay to fire the bias to the driver/finals...
Bias may be on in TX all the time.
I don't like built in drivers but that's just me.
I don't have any experience with HG's so I don't know what they like for drive.

73
Jeff
 
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To me it looks like.... vari... driver on/off.... main on/off
To me it looks like green wire from the SSB delay cap runs towards the front black switch.
RF input power with mini coax goes to the variable and then red teflon out to the driver input transformer wrap.
The bias is turned on when you key up through the yellow wire at the input SO-239 connector running to a fixed voltage regulator in the rear left of the amp to supply steady voltage for the biasing.
Looks alot like a BBI setup for biasing so its not on all the time when un-keyed.
 

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