I have a Galaxy DX-939 which I received new yesterday from
a dealer.
The DX-939 emits a loud high-pitched whine similar to an
analog TV set flyback transformer type of whine -- increases in
pitch with dimmer control rotated towards fully bright, and
increases in amplitude as well.
(MORE details below -- see EL BOARD in this post).
Looking for info and repair options. The EL board is mounted
on the dimmer board and it looks difficult to reach to swap out.
I'm getting too old for this.
-=-=-=
Doesn't look especially feasible to do a return with the dealer;
looking more towards shipping just the transciever (no
accessories) somewhere for a repair job. I'd like to know what
the likely fix is, how difficult it is to do the fix, and (if I
want it done professionally) what I'm looking at for cost.
The radio performs well and I like the feature set.
Also: three potentiometer knobs are quite crooked; they're so
difficult to remove I haven't checked the pot shafts to see if
they are really bent. The packaging did not exhibit any sign of
trauma. The pots behave correctly (makes me suspect only the
knobs, not the pot shafts, are crooked, if that's possible).
I'm considering buying a second radio (new) while this one's
in for repair. The one I have is stock (no tune-up) and the
second radio would also be ordered stock.
Speaking of stock, the stock mic on this rig gives excellent
audio.
EL BOARD
(EL Driver PCB EPT91V131Z)
I looked on cbtricks and have positively identified the EL board
(a small tin box situated on a horse-shoe shaped PCB in proxi-
mity to the front panel meter).
I assume the EL board is an electro-luminescent display driver
of some sort -- it seems to be exciting the star-lite type face-
plate illumination substrate. There is a loud high-pitched whine
emitted from the radio, ostensibly from the EL board. Like the
glue holding it down (solder, expoxy) broke loose during ship-
ping, and now it's transmitting mechanical vibration somewhere
else, and making my ears miserable. Though I don't see how that
would explain it getting into the receive audio as well.
The loud whine increases in both pitch and amplitude as the
dimmer pot is rotated CW towards full brightness. The whine
gets into the RX audio; the squelch squelches this (the whine
in the audio disappears when the radio is squelched; the whine
emitted from the chassis does not). Same with an external
speaker plugged in.
On-air tests report from multiple stations this sound artifact
is not in the transmit audio.
I haven't looked up the IC on the EL board to see exactly what
it does; I'd appreciate a description including any HV (elec-
trical shock) concerns. Reminds me of CCFL (backlight)
for laptop.
The tone 3-position switch does not seem to do anything whatso-
ever; noticing this gave me the idea to take the panties down on
the rig and see if a connector had worked itself loose during
shipping. Couldn't find any problems during this inspection.
Thanks for any thoughts you might give -- appreciated.
gecko
a dealer.
The DX-939 emits a loud high-pitched whine similar to an
analog TV set flyback transformer type of whine -- increases in
pitch with dimmer control rotated towards fully bright, and
increases in amplitude as well.
(MORE details below -- see EL BOARD in this post).
Looking for info and repair options. The EL board is mounted
on the dimmer board and it looks difficult to reach to swap out.
I'm getting too old for this.
-=-=-=
Doesn't look especially feasible to do a return with the dealer;
looking more towards shipping just the transciever (no
accessories) somewhere for a repair job. I'd like to know what
the likely fix is, how difficult it is to do the fix, and (if I
want it done professionally) what I'm looking at for cost.
The radio performs well and I like the feature set.
Also: three potentiometer knobs are quite crooked; they're so
difficult to remove I haven't checked the pot shafts to see if
they are really bent. The packaging did not exhibit any sign of
trauma. The pots behave correctly (makes me suspect only the
knobs, not the pot shafts, are crooked, if that's possible).
I'm considering buying a second radio (new) while this one's
in for repair. The one I have is stock (no tune-up) and the
second radio would also be ordered stock.
Speaking of stock, the stock mic on this rig gives excellent
audio.
EL BOARD
(EL Driver PCB EPT91V131Z)
I looked on cbtricks and have positively identified the EL board
(a small tin box situated on a horse-shoe shaped PCB in proxi-
mity to the front panel meter).
I assume the EL board is an electro-luminescent display driver
of some sort -- it seems to be exciting the star-lite type face-
plate illumination substrate. There is a loud high-pitched whine
emitted from the radio, ostensibly from the EL board. Like the
glue holding it down (solder, expoxy) broke loose during ship-
ping, and now it's transmitting mechanical vibration somewhere
else, and making my ears miserable. Though I don't see how that
would explain it getting into the receive audio as well.
The loud whine increases in both pitch and amplitude as the
dimmer pot is rotated CW towards full brightness. The whine
gets into the RX audio; the squelch squelches this (the whine
in the audio disappears when the radio is squelched; the whine
emitted from the chassis does not). Same with an external
speaker plugged in.
On-air tests report from multiple stations this sound artifact
is not in the transmit audio.
I haven't looked up the IC on the EL board to see exactly what
it does; I'd appreciate a description including any HV (elec-
trical shock) concerns. Reminds me of CCFL (backlight)
for laptop.
The tone 3-position switch does not seem to do anything whatso-
ever; noticing this gave me the idea to take the panties down on
the rig and see if a connector had worked itself loose during
shipping. Couldn't find any problems during this inspection.
Thanks for any thoughts you might give -- appreciated.
gecko
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