[Central-Electronics] Sideband slicer issues

[Jeff]

Well, let me follow up on my own message.  Seems the problem may be the 
PS-1 network.  I'm getting 22 and 44 volts to the grid of 12AT7B (should 
be 10.5 for both.) Voltages going IN to the PS-1 from 12AT7C are right on.

So far I've been unable to find a schematic indicating the values of the 
mica caps in the PS-1.  Does anyone have any notes on rebuilding this?



On 8/15/2015 5:07 PM, Jeff wrote:
> All:
>
> Have a model B sideband slicer.  Works (more or less) and provides a 
> good SSB output on an SX-42.
>
> Two issues however:  First, there is a low level "rumbling" in the 
> audio, whether or not signal is present.  Disconnecting the IF input 
> and just hooking AF out to the phono input does not cure the problem.  
> Have gone through and replaced caps as necessary, including power 
> supply.  Tapped tubes and components, but no changes.
>
> Second, volume output seems low.  Interestingly, when power switch is 
> turned off, the unit's volume out dramatically increases for a few 
> moments until it dies out.  Voltages on the audio amp tube are 
> slightly low, but not extremely so. Also noticed that occasionally 
> when the power switch is turned on, the panel lamp does not light; 
> turning it off and back on again cures the glitch.
>
> Don't know if all problems are connected, but I was looking for some 
> advice before I continue to shotgun components.
>
> Jeff
> WB3JIH
>
>
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