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browning mrk III freq problem
Posted: Saturday 19th Jan 2008, 23:55
by junkman
cannot get trans on freq when on the crystals. only way i can is when i use the glen. the freq counter just jumps around all over the place. i have tried to tune till i'm blue in the face. hope someone can help. junkman p.s. the vfo on the trans will not put it on freq. i changed the air cap. it wiil not stabalise.
Posted: Sunday 20th Jan 2008, 0:18
by The Defpom
what radio is a mrkIII ? I can think of a dozen off the top of my head, please be much more specific, the FULL radio name, exactly what alignment is not working, what have you tried, what test gear do you have, what are the radios symptoms etc.
thank def
Posted: Sunday 20th Jan 2008, 0:45
by junkman
is that any better or need more info??
Re: Browning mrk III freq problem
Posted: Sunday 20th Jan 2008, 4:04
by Rick
There are 3 Browning MK III radios, the Eaglette III, Golden Eagle Mark III, and SST III.
The problem sounds like a weak Oscillator. If the radio is Golden Eagle Mark III.
Check the supply voltage at pins 1 and 6, of V1 (12AX7) and which should be about 150 VDC ? 10%.
Check the output of tube V1 pins 3 and 8 or try replacing the tube,
Also, check the caps C6 and C38 has they maybe leaking.
Re: Browning mrk III freq problem
Posted: Sunday 20th Jan 2008, 4:15
by junkman
Rick wrote:There are 3 Browning MK III radios, the Eaglette III, Golden Eagle Mark III, and SST III.
The problem sounds like a weak Oscillator. If the radio is Golden Eagle Mark III.
Check the supply voltage at pins 1 and 6, of V1 (12AX7) and which should be about 150 VDC ? 10%.
Check the output of tube V1 pins 3 and 8 or try replacing the tube,
Also, check the caps C6 and C38 has they maybe leaking .
thanks rick. it is a golden eagle ssb.iwill chk those.i did replace the 12ax7,replaced the air cap for the vfo, replaced the 6.048 crystal. works fine when i use the glen slider. jack
Re: Browning mrk III freq problem.
Posted: Tuesday 22nd Jan 2008, 3:55
by Rick
First set the radio up like so
Channel Selector to channel 12
VFO to 1/3 mesh
Mode to AM
Turn on and let the radio warm-up for 2 minutes
With a VTVM connect to Pin 9 of V6 (6GH8), adjust L5 for ? 8 Volts.
With a frequency counter and a 10 to 1 probe, connect the counter to Pin 2 of V6 (6GH8), you should see the mixer frequency which should be 21.4585 MHz, if this is ok connect the counter to Pin 1 of V3 (6CB6), you should see the output frequency which should be 27.105 MHz.
At the point let us know how you get on.