On Dec 16, 8:36*am, Dave wrote:
BCBlazysusan wrote:
As someone that has been in the hobby for only 12-13 yrs I feel I
should know the answer to this but I don't. What is the reason for
having a "stand by" switch?

I have always had a couple theories and or questions about it? First
the question. I won't ask about the stand by on tube radios. But is it
better for me to just put my receiver on stand by if I don't want to
hear it or I get a phone call etc. etc.? Electronically wise is it OK
for your radio to be on stand by for an extended period of time like
say a half hour or is this bad for your receiver? Is it better for you
to just shut down the receiver all together or just turn the volume
down? Follow me?

I always thought the stand by was for if you were transmitting on
another piece of equipment and you didn't want reverb for lack of a
better word going through your receiver. For the tube type radios, is
it harder or more of a pull electrically on the tubes itself? I am
looking forward to the responses.

Think of it as a mute button.- Hide quoted text -

- Show quoted text -

Yes Dave I do. But I just wanted to know if there would be extra pull
created if it was on there for an extended period of time. On the
DX394 at least when you put it on stand by it brings the signal gain
down to nothing so it's actually doing something more electronically
than just muting it IMO if that makes sense. ;-) Thanks for the
response.

On Dec 17, 1:00*am, BCBlazysusan wrote:
On Dec 16, 8:36*am, Dave wrote:





BCBlazysusan wrote:
As someone that has been in the hobby for only 12-13 yrs I feel I
should know the answer to this but I don't. What is the reason for
having a "stand by" switch?

I have always had a couple theories and or questions about it? First
the question. I won't ask about the stand by on tube radios. But is it
better for me to just put my receiver on stand by if I don't want to
hear it or I get a phone call etc. etc.? Electronically wise is it OK
for your radio to be on stand by for an extended period of time like
say a half hour or is this bad for your receiver? Is it better for you
to just shut down the receiver all together or just turn the volume
down? Follow me?

I always thought the stand by was for if you were transmitting on
another piece of equipment and you didn't want reverb for lack of a
better word going through your receiver. For the tube type radios, is
it harder or more of a pull electrically on the tubes itself? I am
looking forward to the responses.

Think of it as a mute button.- Hide quoted text -

- Show quoted text -

Yes Dave I do. But I just wanted to know if there would be extra pull
created if it was on there for an extended period of time. On the
DX394 at least when you put it on stand by it brings the signal gain
down to nothing so it's actually doing something more electronically
than just muting it IMO if that makes sense. ;-) Thanks for the
response.- Hide quoted text -

- Show quoted text -

Now that you have mentioned the receiver model (Radio Shack DX-394),
answers can be a bit more specific.

The DX-394 standby mode disconnects the voltage supply to the entire
RF chain while leaving the audio chain functioning so that key presses
will beep. It also locks the microcontroller from acting on any key
press except Power; the triple beep response indicates the lockout. I
daresay that this provides some added measure of protection to the
receiver front end that an audio mute would not, if used in
conjunction with a ham transmitter. Either would eliminate the
feedback risk. Normally, a feedline T/R relay would provide ample
isolation for receiver protection but sometimes the receiver may be on
an unswitched antenna not shared with the transmitter and the mutual
coupling would be higher than the relay isolation.

The standby switch is not very convenient because it neither controls
an external device nor does the receiver provide an interface for an
external control. I modified one of mine for that purpose so that one
switch would toggle the T/R relay and transmitter and receiver status.
Moreover, the DX394 Standby is but the leftmost position on the 6-
position Mode switch - hardly convenient for T/R control from any mode
other than the adjacent position (AM). So I added a separate front
panel Standby switch. The way the 394 Mode switch works makes me think
that it may have been intended to be Aux, not Standby, and since the
former may have been scrapped in the design process, we got the
somewhat useless Standby Mode on that switch.

If not already, join the big DX-394 user group at
http://groups.yahoo.com/group/RADIOSHACKDX394/ ...

Tom