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Radio Make and Model: MAJOR 788
PCB Number: PTBM133A4X
PLL Number: PLL02
Test gear available: TEST METER
Symptoms: no tx or rx

What is working: it lights up

What has been tried: nothing as yet dont want to break it even more

Did it suddenly happen ?: no was brought like this
Anything else that may be of help?:

Hi guys i brought this because ive been after one for years now to add to my collection of majors, it lights up changes channels etc it has no tx has ive tried it sat next to another radio and vice versa any help would be greatful
Right thought i would have a bash got nothing to loose,so i had a play with the vco i did get some locals to me and the radio did tx but only halfway on the signal meter and also if i changed channel they would be on the next one too , then its gone again wont key up,ive checked voltage on pll02 pin 1 and i get 5.6v

Check the AVR transistor Q34, it's a darlington transistor 2SD837 or replace it with a new one to be on the safe side, also check the zener diode at it's base pin at the other side of L17.
I don't know the radio but that's what I'd start with as it's the voltage regulator.

hi zodiac (dave????) i have read somewhere else about the darlington q34 so i will try this next, i think the board is the same a mm3 and the concorde 3 if this helps

Yes it is the same board but I've been lucky and never had to work on one yet.

hi guys just to let you know it was the vco that was at fault,good mate of mine has done but thanks dave for your help