148gtl mod 1990

[kaos513]

Upper and lower freqs and a band switches i suppose? What is the frequency range?? Just curious. They are nice radios and actually even nicer when they haven't been touched at all!! But for the money you spent as long as the radio works properly you did fine for $40. Have fun with it!!

 

[kaos513]

thinking of going back to stock but some idiot scraped one of the pll traces to do that mod

 

[camaro1]

if it works fine and is on frequency and good sound/modulation, just use it the way it is,, you got a good deal if it all works fine.

 

[sonoma]

for the channel mod you have to cut 2 traces depending on what channels was wanted. just use it as it is as camero1 mentioned. most shops charge 50.00 to put channels in a radio. some even more.

 

[kaos513]

for the channel mod you have to cut 2 traces depending on what channels was wanted. just use it as it is as camero1 mentioned. most shops charge 50.00 to put channels in a radio. some even more.

yeah im keeping it that way

 

[kaos513]

thanks for all the help

 

[sonoma]

you will be happy with the 148. I like them the best for talking SSB

 

[kaos513]

The resistor on the clarifier B+ wire decreases slide (or can drop +13.8V down to +8V), the capacitor helps stabilize that voltage out of the resistor. Very weird mod, almost looks like they tapped directly to the +13.8V.... can't tell 100% for sure, tho. Would need a better closeup pic of the cap/resistor and where they are soldered to.

Obviously, the easiest way to get +8V is to either tap off of pin 3 on the MB3756 voltage regulator IC, or go to the + side of C84, which is the +8V feed for the PLL control voltage.


~Cheers~

 

[kaos513]

I Have a question the clarifier was off about 9 oclock so i aligned the clarifier to the centered was i wrong to align the claifirer back to centered?

 

[Robb]

I Have a question the clarifier was off about 9 oclock so i aligned the clarifier to the centered was i wrong to align the claifirer back to centered?

Depends if the clarifier's freq range has been extended or not. Normal range is about 1200hz lock to lock. If the freq range has been extended well beyond that, then the clarifier center won't be on center. However, if the clarifier freq range is normal, then USB/LSB/AM can be centered w/o a problem.

 

[kaos513]

Regular cb frequency was at 9 oclock so i centered it and aligned it for proper cb frequency,the mod i showed in this thread seems like some sort of frequency mod?

 

[kaos513]

I unmoded the radio back to stock the only problems i have is no audio and the clarifier dosent work at all but it is right on frequency,

 

[kaos513]

Has power recieves transmits great but no modulation on am,usb and lsb

 

[Robb]

If it had audio before you changed things; then you will need to re-trace yours steps.
Great way to learn more and connect to the schematic.

 

[kaos513]

I will be putting up a youtube video so can someone see my problem as i lost am power as well but then i checked ic4 all voltages are correct its strange there is not am power now and no modulation but it does recieve.i really dont know where the clarifier wires goes as well.