pforbes
Member
I've found something rather odd in our Quantars that I think some of you'd like to know about.
For the last five or so years our 16 sets of dual Back-to-back Quantars have been randomly plagued by weird, variable and very intermittent problems. One might not want to key up its mate and/or vice-versa. Then they might be individually, instead of them both, on the wrong channel. Most times, the problem would disappear after removing the door, re-seating the WL or the SCM or some other mechanical shock inducing action.
Sometimes the problem would go away right before my eyes but return a month or so later.
In one particular instance I managed to measure the cross-connected COR/PTT line during an attempted PTT and found 1.7 VDC. Not the .004 or so that was expected. Thought the K100 was bad. Replaced it. Problem returned two months later. Same symptoms. Then suspected loose 50 pin plugs due to loose Velcro strap. Ty-wraped the heck out of them. Still no change. However,
After removing a back-plane in bright sunlight, I discovered the 50 pin J-17, which our configuration makes use of, is not soldered. Our configuration utilizes 13 of them. Neither are the PSU, PA or the two db25 sockets! Someone at Motorola, in their infinite wisdom, decided square pins pushed into tight round holes was sufficient.
Very carefully soldering the 50 pins solved the issue right there on the spot.
Granted, our Quantar pairs are installed in diesel and gas Econoline style vans, operating as local Repeaters with a Duplex Base cross-connected to get the scene radio activity back to the Comm Ctr. They may travel around town a few times a day and only get put into use once a week or two. And yes, the environment they're in is somewhat different than that of your typical Fixed Radio Site, BUT, Motorola did sell them to us in that exact configuration for that intended installation and use.
If any of you folks out there happen to have Quantar get-ups a bit out of the ordinary, like ours, and have noticed any weird goings on, you might want to try soldering the affected sockets.
For the last five or so years our 16 sets of dual Back-to-back Quantars have been randomly plagued by weird, variable and very intermittent problems. One might not want to key up its mate and/or vice-versa. Then they might be individually, instead of them both, on the wrong channel. Most times, the problem would disappear after removing the door, re-seating the WL or the SCM or some other mechanical shock inducing action.
Sometimes the problem would go away right before my eyes but return a month or so later.
In one particular instance I managed to measure the cross-connected COR/PTT line during an attempted PTT and found 1.7 VDC. Not the .004 or so that was expected. Thought the K100 was bad. Replaced it. Problem returned two months later. Same symptoms. Then suspected loose 50 pin plugs due to loose Velcro strap. Ty-wraped the heck out of them. Still no change. However,
After removing a back-plane in bright sunlight, I discovered the 50 pin J-17, which our configuration makes use of, is not soldered. Our configuration utilizes 13 of them. Neither are the PSU, PA or the two db25 sockets! Someone at Motorola, in their infinite wisdom, decided square pins pushed into tight round holes was sufficient.
Very carefully soldering the 50 pins solved the issue right there on the spot.
Granted, our Quantar pairs are installed in diesel and gas Econoline style vans, operating as local Repeaters with a Duplex Base cross-connected to get the scene radio activity back to the Comm Ctr. They may travel around town a few times a day and only get put into use once a week or two. And yes, the environment they're in is somewhat different than that of your typical Fixed Radio Site, BUT, Motorola did sell them to us in that exact configuration for that intended installation and use.
If any of you folks out there happen to have Quantar get-ups a bit out of the ordinary, like ours, and have noticed any weird goings on, you might want to try soldering the affected sockets.
