Copper Talk » Ask The Tech » Radio's Mobile » Archived Messages » Older 148 GTL « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Old_man
New member
Username: Old_man

Post Number: 1
Registered: 9-2006
Posted on Sunday, September 24, 2006 - 3:55 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have had this radio since about 1988 and all the mods were done before purchase. My question is, it has sat unused for a couple of years and the recieve seems to be low or tight. Anyone have any ideas or recieve mods to loosen it up a bit?

Thanks,
Mike
Top of pagePrevious messageNext messageBottom of page Link to this message

Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2103
Registered: 9-2004
Posted on Sunday, September 24, 2006 - 10:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

first, try an alignment. not a peak and tune. anyone that advertises using that term should be avoided.
remember that the sunspot cycle is at its lowest point right now, and CB has steadily declined in popularity, so you may have a great receiver, and there is just no one out there to hear.
your antenna system may also be different now.
if you are using the same antenna, but havent used it for a few years, i would much more suspect aluminum corrosion, and or bad coax before suspecting the radio.

electrolytic capacitors do dry up, and can cause this symptom, but is is less likely on a radio that has not been used excessively.
if you used to leave your radio on for extended periods of time, like more than 8 hours at a time, then you might suspect the caps. also, if the antenna and alignment are perfect suspect a bad cap.

if you really want a good receiver mod for that radio, replace TR14 with a 2SC2999 or an NTE107.
put the transistor you just removed (2SC1674) in place of TR19.
replace D1 and D2, D21 and D22, with 1N6263 or NTE583 diodes.

good luck,
matt
Top of pagePrevious messageNext messageBottom of page Link to this message

Old_man
New member
Username: Old_man

Post Number: 2
Registered: 9-2006
Posted on Monday, September 25, 2006 - 3:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks for the info Matt,
It is a new antenna, and using this on base station. Last night, checked between 2 radios sitting side by side for receive operation and the cobra was working great. I will try that receive mod.
Thanks,
Mike

Add Your Message Here
Post:
Username: Posting Information:
This is a private posting area. Only registered users and moderators may post messages here.
Password:
Options: Enable HTML code in message
Automatically activate URLs in message
Action: