I don't normally get to work on these fine, old radios. But one came to me just the other day from a local trucker op that brings me his radios from time to time.
The amount of glue that holds the toroids in the back of the radio is daunting to remove. However, I have found that using the soldering iron will soften it up really fast and w/o damaging the board or the parts themselves. Makes removal from the board much easier. Problem is: what do I use to remove the glue from the toroid after it is out? Another problem: what kind of glue can I use to refasten it to the board that won't become conductive? Epoxy? Certainly not hot glue?!? I know; old clewing gum obtained from the bottom of a restaurant table?!?
lol . . .
Also had a problem with the heat sink getting too hot And something I have NEVER seen before: the speaker was getting so hot you couldn't keep your hand on it - and still worked!.
Turned out the MRF-477 had perished. Could it be because the person that installed it left out the mica insulator?!?
No doubt that it will need to get re capped. But there are nearly ~70 electrolytics on board. Figuring that replacing 15 caps/hour/average would mean close to/exceeding four and a half hours labor. Not to mention the fact that the cap kit will be nearly twice the price. Doesn't add up to a cheap bill. Gonna have to break the news to the customer. Guesstimate the bill will be $40 for the caps, $90 for cap replacement/labor, another $45 for a MRF-497MP (replaces the MRF-477 and can be purchased from 'RF Parts'). Then alignment will be another $50. That's 225 buckereenies w/o anything else it might yet need. If I charge for glue removal (I should); that will be another $30.
Nice old radio; but not a cheap date by any means!
The amount of glue that holds the toroids in the back of the radio is daunting to remove. However, I have found that using the soldering iron will soften it up really fast and w/o damaging the board or the parts themselves. Makes removal from the board much easier. Problem is: what do I use to remove the glue from the toroid after it is out? Another problem: what kind of glue can I use to refasten it to the board that won't become conductive? Epoxy? Certainly not hot glue?!? I know; old clewing gum obtained from the bottom of a restaurant table?!?
lol . . .
Also had a problem with the heat sink getting too hot And something I have NEVER seen before: the speaker was getting so hot you couldn't keep your hand on it - and still worked!.
Turned out the MRF-477 had perished. Could it be because the person that installed it left out the mica insulator?!?
No doubt that it will need to get re capped. But there are nearly ~70 electrolytics on board. Figuring that replacing 15 caps/hour/average would mean close to/exceeding four and a half hours labor. Not to mention the fact that the cap kit will be nearly twice the price. Doesn't add up to a cheap bill. Gonna have to break the news to the customer. Guesstimate the bill will be $40 for the caps, $90 for cap replacement/labor, another $45 for a MRF-497MP (replaces the MRF-477 and can be purchased from 'RF Parts'). Then alignment will be another $50. That's 225 buckereenies w/o anything else it might yet need. If I charge for glue removal (I should); that will be another $30.
Nice old radio; but not a cheap date by any means!
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