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tony tony is offline
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Default Pioneer sx-727 FM problem

On Feb 10, 1:52*pm, Jeff Urban wrote:
If there's no noise between stations with the muting off it's probably
oscillating. That would maybe indicate filters or bypass caps. If the
frequency actually drifts, assuming it has ONE fault which is usual,
look around theFMoscillator or mixer stages.

I think buzz between AM stations is just about normal these days,
unless you specifically noticed a difference at the same time theFM
fault showed up.

Actually RF is not really my strong suit, but it's still electronics.
If that reciever uses discrete transistors for theFM, it might be a
bit hard to find someone who really remembers how to work on it. That
reciever is old enough for a pension, but by all means try to keep it
alive.

J


Thanks for the info.
I looked at the AWR-011, Power supply unit board.
Anyone know what the tolerance should be on these voltages.
For the AWR-011, Power Supply unit board
the schematic says
pin 2,5,6,7 12.5v, 30v, 30v, 36v
I'm measuring
pin 2,5,6,7 10.5v, 27.5v, 27.5v, 33v

Is this within tolerance?

Also anyone know what the output of the big transformer
(ATT-050)should be
Nothing listed on the schematics.
I'm measuring
pins 13, 12, 10, 3 26vAC, 25.5vAC, 35v AC, 0 (AWR-011 board).

Thanks.