I am in the process of adjusting a restored BC-312. Reading the book, I could
not determine whether the oscillator must oscillate at +470 kHz or - 470kHz with
respect to the receive frequency.

The oscillator adjustment range is wide enough that I can set it at either
positions, so I need to know which of the two is correct (so as to have the dial
scale showing the real receive frequency as close as possible).

Also, I would need to know whether it works the same on all bands.

Thanks in advance for your help.

73

Tony I0JX

On Jul 13, 5:34 pm, "Antonio Vernucci" wrote:
I am in the process of adjusting a restored BC-312. Reading the book, I could
not determine whether the oscillator must oscillate at +470 kHz or - 470kHz with
respect to the receive frequency.

The oscillator adjustment range is wide enough that I can set it at either
positions, so I need to know which of the two is correct (so as to have the dial
scale showing the real receive frequency as close as possible).

Also, I would need to know whether it works the same on all bands.

Thanks in advance for your help.

73

Tony I0JX

================================
The local oscillator operates on the high side of the signal frequency
on all bands. --Ed

"Ed Engelken" ha scritto nel messaggio
...
On Jul 13, 5:34 pm, "Antonio Vernucci" wrote:
I am in the process of adjusting a restored BC-312. Reading the book, I could
not determine whether the oscillator must oscillate at +470 kHz or - 470kHz
with
respect to the receive frequency.

The oscillator adjustment range is wide enough that I can set it at either
positions, so I need to know which of the two is correct (so as to have the
dial
scale showing the real receive frequency as close as possible).

Also, I would need to know whether it works the same on all bands.

Thanks in advance for your help.

73

Tony I0JX

================================
The local oscillator operates on the high side of the signal frequency
on all bands. --Ed

Thanks Ed.

In the meantime a local guy had told me that for bands A, B and C the oscillator
should be set higher than the operating frequency, whilst for bands D, E and F
lower.

What is your degree of confidence on the issue?

73

Tony

"Antonio Vernucci" wrote in message
...
I am in the process of adjusting a restored BC-312. Reading
the book, I could not determine whether the oscillator must
oscillate at +470 kHz or - 470kHz with respect to the
receive frequency.

The oscillator adjustment range is wide enough that I can
set it at either positions, so I need to know which of the
two is correct (so as to have the dial scale showing the
real receive frequency as close as possible).

Also, I would need to know whether it works the same on
all bands.

Thanks in advance for your help.

73

Tony I0JX


This receiver is covered in the military manual TM
11-850 which can be downloaded from the BAMA site. It
appears to be available from some other free sites, a Google
serach found a lot of hits.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Richard Knoppow" ha scritto nel messaggio
m...

"Antonio Vernucci" wrote in message
...
I am in the process of adjusting a restored BC-312. Reading the book, I could
not determine whether the oscillator must oscillate at +470 kHz or - 470kHz
with respect to the receive frequency.

The oscillator adjustment range is wide enough that I can set it at either
positions, so I need to know which of the two is correct (so as to have the
dial scale showing the real receive frequency as close as possible).

Also, I would need to know whether it works the same on all bands.

Thanks in advance for your help.

73

Tony I0JX


This receiver is covered in the military manual TM 11-850 which can be
downloaded from the BAMA site. It appears to be available from some other free
sites, a Google serach found a lot of hits.


--
---
Richard Knoppow
Los Angeles, CA, USA


As you will note re-reading my message more carefully, I have the book, but I
could not find the required information in there. I will search it again and see
whether it is written somewhere.

Tony I0JX

The BC-348 works as you described: The LO is on the high side for the
three lowest bands, and on the low side for the top three bands. The
BC-312 is a different animal. The LO is on the high side on all six
bands. --Ed

"Ed Engelken" ha scritto nel messaggio
...
The BC-348 works as you described: The LO is on the high side for the
three lowest bands, and on the low side for the top three bands. The
BC-312 is a different animal. The LO is on the high side on all six
bands. --Ed

Ed,

I re-read the book carefully, and I found the explanation in the adjustment
section, not in the theory of operation section as I was expecting.

At page 126 it clearly states that the oscillator is on the low side for the
three higher frequency bands and on the high side for the three lower frequency
bands.

Sorry for the useless noise, I should have read the book more carefully.

Thank you for your availability anyway.

73

Tony I0JX

On Jul 14, 5:45 pm, Ed Engelken wrote:
The BC-348 works as you described: The LO is on the high side for the
three lowest bands, and on the low side for the top three bands. The
BC-312 is a different animal. The LO is on the high side on all six
bands. --Ed
================
Forget that!! I just checked my notes and I got my BC-312 and BC-314
confused. Your friend is correct. It is the LO higher on bands A, B,
and C and lower on the three higher bands. Sorry for the confusion. --
Ed