|
Post by 238 on Aug 11, 2019 20:34:19 GMT -5
Put a 25 in my big truck. Every thing seemed ok at first, but then the receive would come & go. Acted like wire was broken in the mike plug, but tried 3 mikes, same thing. Taped top of radio receive would come & go. Took it back out. Hooked it up at home & if you took a plastic probe an touch any place in the left front side it would go & come. You did not have to mash hard just tap it lightly. If you have the radio right side up, it is anywhere in the left front quarter of the board. 238
|
|
Sandbagger
Administrator/The Boss
Posts: 6,247
|
Post by Sandbagger on Aug 11, 2019 21:34:06 GMT -5
Put a 25 in my big truck. Every thing seemed ok at first, but then the receive would come & go. Acted like wire was broken in the mike plug, but tried 3 mikes, same thing. Taped top of radio receive would come & go. Took it back out. Hooked it up at home & if you took a plastic probe an touch any place in the left front side it would go & come. You did not have to mash hard just tap it lightly. If you have the radio right side up, it is anywhere in the left front quarter of the board. 238 It's pretty obvious that you have an intermittent connection somewhere. The fun will be tracking it down. You'll have to pull the covers off and poke lightly until you can make the problem happen. Most likely you have a cold solder joint somewhere.
|
|
|
Post by 238 on Aug 12, 2019 7:00:55 GMT -5
I checked it with covers off. Anywhere you touch in the left front 1/4 of the board will make it come & go. You can make it do it if you loosen the screw that mounts the board to the case. The one that is on the left front side screw. I re solder the joints that connected at that screw. I reckon i will have to start doing a few joints at a time till i find the right one. 238
|
|
|
Post by bobcat4109 on Aug 12, 2019 9:12:29 GMT -5
Not sure how you are doing the touching... but use something light and non-conductive.... like a chopstick. Then be very very gentle moving around and gently tapping wires and components to try to localize the problem a bit.
|
|
Sandbagger
Administrator/The Boss
Posts: 6,247
|
Post by Sandbagger on Aug 12, 2019 11:21:01 GMT -5
I checked it with covers off. Anywhere you touch in the left front 1/4 of the board will make it come & go. You can make it do it if you loosen the screw that mounts the board to the case. The one that is on the left front side screw. I re solder the joints that connected at that screw. I reckon i will have to start doing a few joints at a time till i find the right one. 238 A good magnifying glass might help you to visually locate the problem.
|
|
|
Post by dilbert on Aug 12, 2019 11:45:59 GMT -5
My iPhone has a magnifying option that really works well. Has a light and can freeze frame it. I use it a lot for tiny work.
|
|
|
Post by bobcat4109 on Aug 12, 2019 14:45:31 GMT -5
My iPhone has a magnifying option that really works well. Has a light and can freeze frame it. I use it a lot for tiny work. That is no kidding!!! I've used my phone many a time for tiny TINY print. Just snap as close a pic as I can, then open the pick and spread it out to magnify. Great point!
|
|
|
Post by 321 treeclimber on Aug 12, 2019 16:58:45 GMT -5
You have a cracked ground to chassis solder joint. Resolder all unions that connect board to chassis
|
|
|
Post by 238 on Aug 12, 2019 21:21:20 GMT -5
I am going to re solder all the board to chassis screws. Then if that dose not help i will start on the board a few joints at a time. I use a plastic diddle stick to touch the board. 238
|
|
|
Post by 321 treeclimber on Aug 12, 2019 23:06:53 GMT -5
10-4. These guys are right. And it could be anything that has a broken connection but your problem sounds like the same thing i had with an early mobile unit, cracked joints for grnd to chassis. I had two identical radios do it.
|
|
|
Post by 321 treeclimber on Aug 12, 2019 23:09:52 GMT -5
Also if you gently flex or twist the chassis you may see it happen and discover the hairline crack. 321
|
|
|
Post by bobcat4109 on Aug 13, 2019 14:28:14 GMT -5
The trick though is.... easy does it on the touches! Often flexing of the chassis or board...flexes a NUMBER of wires/solder joints/component leads/through holes... and it is tough to determine what area holds the problem. Develop a REAL light touch...and just probe around......
|
|
|
Post by 321 treeclimber on Aug 13, 2019 18:22:03 GMT -5
10-4 . Your right. Easy does it.
|
|