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kj4mqa · #1 07-01-2009, 09:28 AM

i have a golden eagle mark 3
works fine on am and usb.off freq. by 2 kc an am.
rec on lsb but no tx any idea`s?
ive replaced some tubes still no tx on lsb.

73s kj4mqa bill

kj4mqa@yahoo.com

unit_399 · #2 07-01-2009, 05:03 PM

Bill -

It looks to me like the carrier oscillator V1a (12AX7) is dead in the LSB mode, or the Mode Switch has an open contact in the LSB position. Since the oscillator is working in AM and USB, the tube is ok. You can check for oscillator output by putting a scope probe on the side of C6 that is connected to the mode switch. If no oscillation in LSB, check crystal CR2 (5.6480 mhz), and make sure tuning cap C2 isn't shorted. If these check OK, then check the contacts on the mode switch in the LSB position. Check all the solder joints in the area too. Good Luck.

- 399

kj4mqa · #3 07-01-2009, 06:29 PM

Quote:

Originally Posted by unit_399

Bill -

It looks to me like the carrier oscillator V1a (12AX7) is dead in the LSB mode, or the Mode Switch has an open contact in the LSB position. Since the oscillator is working in AM and USB, the tube is ok. You can check for oscillator output by putting a scope probe on the side of C6 that is connected to the mode switch. If no oscillation in LSB, check crystal CR2 (5.6480 mhz), and make sure tuning cap C2 isn't shorted. If these check OK, then check the contacts on the mode switch in the LSB position. Check all the solder joints in the area too. Good Luck.

- 399

ok i will check it out. thanx 4 the info.
73s kj4mqa bill

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golden eagle mark 3 no lsb