Super Galaxy Radio, Warble on SSB

[15mini]

could the MOD be clipped???

On AM its super, but on SSB it warbles like hell. but when I drop the mic gain, it talks good.

Might be the mod limiter is clipped.


any suggestions????

[521 Houston]

Could be overmodulation, or it could be related to another problem too.

I found this info on another forum i'm on, so thought i'd post it here in case some others are having similar problems...

Subject: Cobra 148/Uniden Grant LT/Uniden Grant XL

Low Voltage mod as in the radio becoming garbled or
shifting freq. when used in a car?? I have trouble
with almost all of mine when my Power Wagon is
idling..lol I was always wondering if there was
anything I could do..Even my newer Grant XL does it..
Tony

-----------------------------------------------------------
Yup , the MB3756 is the wrong component for a 12V mobile situation .
This is one of the few design flaws with the 8719 chassis. The minimum
input voltage threshold is too high on this chip and it needs to be
replaced .

My simple solution that works every time is to replace this chip with a
relay and a 7808 .

Once this is done , you can key down your linear with the car off and
not scramble

1) remove the MB3756 chip and save the plastic screw and nut.
2) get a T0-220 mica , 7808 regulator , 10uF 10-50v lectro , 0.01uF
mylar.
3) like the mod regulator , twist on the 10uF to the ground and output
legs and the 0.01uF to the ground and input leads then solder on three
lengths of wire to each leg and grease / bolt it to the existing hole
on the wall just above the empty 3756 slot.
4) wire the ground lead to the ground foil , input lead to pin 2
location on board , output lead to pin 1 location on board.
5) 12V coil SPDT relay double sided taped to a wall , put spike diode
across coil (1n4004) , wire common switch contact to pin 1 location on
board , NC switch contact to pin 6 location on board and wire NO switch
contact to pin 8 location on board.
6) wire cathode side of coil to +12V on the radio power switch .
7) disconnect the receive wire from the mike jack and tape up.
wire mike jack receive (at jack) to the anode side of the relay coil.

you're done and no more "low voltage" problem

Yeah , it uses a relay but quickly and simply fixes this very annoying
problem. Dave

Hope someone finds this info useful!

[BigBopper]

When you get wabble on most Galaxy Radios, is due to the fact the modulation limiter has been removed

[521 Houston]

When you get wabble on most Galaxy Radios, is due to the fact the modulation limiter has been removed

Yeah.... what Bopper said.... LOL!

[15mini]

Do you kknow where this limiter is Bopper? I have an extra galaxy for parts. Hey that post you added houston came across it with the Super Galaxy power prob. It was a bad on off switch.

Thanx, aloha 1-5.