[Heathkit] HG-10 -VFO power supply, DX-60B

[Kenneth G. Gordon]

> Would it help to replace the filter caps in the DX-60B  with a larger
> capacitance value to help stabilize voltage to the VFO?

Probably not.

> 
> Also, this DX-60B has an electronic T-R switch modification in  it. This 
> involves an added tube, and was described in a QST article. I  could never
> really use the T-R switch, though, because the transmitter signal  still got
> through to the receiver so strong it was scary. Anybody familiar with  this
> modification?

I am familiar with TR switches: IFF the TR switch is operating properly, 
the signal you hear in the receiver, although still quite strong, will be 
below the level at which it will harm the receiver.

The BEST TR switches include a way to reduce receiver gain at key 
down to prevent blowing your ears off.

Although TR switches can generate a lot of harmonics, thus causing 
TVI if you don't include a good low-pass filter between your antenna 
coupler (if you use one) or transmitter, and antenna, most modern TV 
signals are carried by cable and thus are pretty immune to the TVI 
caused by TR switches.

I would check the level of the signal into your receiver from the TR 
switch with a scope at key down, and if it is reasonable, I would use it 
anyway, if your ears can stand it.

A good audio limiter will help immensely. There are several that are 
shown in old handbooks that are both simple and effective.

Ken Gordon W7EKB