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xj4life2
05-21-2012, 10:39 AM
Ok I have a uniden 78 that has been working fine but now has developed and issue, When I key down the TX light comes on but the needle doesnt move or swings in reverse, the crazy thing is , not all the time but seems to be increaseing in frequency. Sometimes I can get it to work by repetedly keying the mic. Coincidence? so do we have a voltage problem , mic problem, transmit or finals ? I'm not a CB repair kinda guy so this needs be a simple fix or I'm gonna trash this one a get another. Oh, when it does work as it should the SWR is about 1 to 1 through all 40.
Mudderoy
05-21-2012, 01:56 PM
Ok I have a uniden 78 that has been working fine but now has developed and issue, When I key down the TX light comes on but the needle doesnt move or swings in reverse, the crazy thing is , not all the time but seems to be increaseing in frequency. Sometimes I can get it to work by repetedly keying the mic. Coincidence? so do we have a voltage problem , mic problem, transmit or finals ? I'm not a CB repair kinda guy so this needs be a simple fix or I'm gonna trash this one a get another. Oh, when it does work as it should the SWR is about 1 to 1 through all 40.

Long shot. Does it click like there is a mechanical relay internally? The contacts could be dirty.
xj4life2
05-21-2012, 02:06 PM
when you key down it makes a "thud" in the speaker like its doin what it should but the needle either goes to the left or doen't move at all. Transmit light comes on and all seem normal. I have it on a plug in to the accesory plug (lighter) so i'm wondering if voltage may be an issue, but has only started doin this in the last week. but like I said the match seems good when it works so i dont think its an antenna issue. Mic or radio but which one ??
Mudderoy
05-21-2012, 02:08 PM
when you key down it makes a "thud" in the speaker like its doin what it should but the needle either goes to the left or doen't move at all. Transmit light comes on and all seem normal. I have it on a plug in to the accesory plug (lighter) so i'm wondering if voltage may be an issue, but has only started doin this in the last week. but like I said the match seems good when it works so i dont think its an antenna issue. Mic or radio but which one ??

Do you have a watt meter? I suspect you're not getting 3+ watts out when it's doing that. Could be the finals.
xj4life2
06-05-2012, 11:43 AM
Just as an update , ya , I smoked the finals , fortunutly its still under warrenty. Currently running a cobra 25ltd. working fine at this time. need to get the "extras" hooked up to it.
Mudderoy
06-05-2012, 11:45 AM
Just as an update , ya , I smoked the finals , fortunutly its still under warrenty. Currently running a cobra 25ltd. working fine at this time. need to get the "extras" hooked up to it.

If the "extras" is a RF power amplifier that could be what smoked your finals. :D
xj4life2
06-06-2012, 10:44 AM
If the "extras" is a RF power amplifier that could be what smoked your finals. :D

Uhhhh who me with one of those? :rolleye0012: Pretty sure that wasn't it this time :innocent0002:
Mudderoy
06-08-2012, 10:30 AM
Uhhhh who me with one of those? :rolleye0012: Pretty sure that wasn't it this time :innocent0002:

Usually the amp catches the brunt of the RF coming back in, but ...
xj4life2
06-29-2012, 05:20 PM
Some high praises to Uniden , sent radio back under warrenty ...... They sent me a fac refeb in the box with a new warrenty and all . Now thats customer service !!!!