Thanks. Surprisingly it's still showing up for about $5. I took the easy and quick route and just added a #22 yellow Teflon-covered wire around it. Very obvious. Anyone who has to remove either board will just have to unsolder that wire first.
Bob M. ====== --- Ralph Messer <[EMAIL PROTECTED]> wrote: > Bob > > My manual shows 09-80103m05 is the part number for > the female > connector mounted on the interconnect board. > > Ralph > KA4DKJ > ----- Original Message ----- > From: Bob M.<mailto:[EMAIL PROTECTED]> > To: > [email protected]<mailto:[email protected]> > > Sent: Tuesday, February 05, 2008 5:04 PM > Subject: Re: [Repeater-Builder] Re: Low-band > MaraTrac Squelch Pots > > > After soldering a wire from point-A to point-B, I > thought I fixed the problem, but it persisted. > > I scoped all the signals on J21 and found that the > one > on pin 8 was going away. The connection from the > audio > board, at the back of the pin-side of the > connector, > to the logic board, and even the interconnect > board, > was going open when the squelch failed. No > detected > audio, no squelch operation. > > The socket at pin 8 of J21 seems to be defective. > It's > not gripping the pin coming in from the audio > board. I > can put a resistor lead into any of the other > holes > and feel the contact gripping the lead, but on pin > 8 > it just wobbles around. > > I could replace the connector IF I had a part > number > and IF Motorola still had one. It's an 18-pin > female > dual row, right-angle, 0.100 inch type. I didn't > find > one on Mouser, but did find a 2mm connector of the > right style. > > The alternative is to solder a wire from the > interconnect board directly to the pin 8 of J21 on > the > audio board. This would bypass the connector and > insure it never fails again, but removing the > board > would require unsoldering the wire. > > I didn't expect this kind of failure. I have a > feeling > it was a defective part installed at the factory, > and > if the radio never had the need for carrier > squelch, > no one ever cared about it. Also, the connection > would > be good once in a while, so it might have worked > when > it left the factory and just decided to fail later > in > life. > > Bob M. > ====== > --- "Bob M." > <[EMAIL PROTECTED]<mailto:msf5kguru%40yahoo.com>> > wrote: > > > Problem temporarily solved. While tracing the > > signals > > around U1103, I found no Detected Audio coming > into > > pin 8 of J21, however when I pushed on the pin > just > > a > > bit, the radio would then squelch up and the pot > > worked like it should, along with the one on the > > audio > > board which was also dead. I pulled the audio > board > > but didn't find anything wrong. I resoldered pin > 8 > > and > > put it back and it worked fine, until I started > > bending the interconnect board near J21 in the > front > > of the radio. Now it's intermittent, so it looks > > like > > I'll have to pull that board and find the > fractured > > foil. Doesn't look like an easy board to pull > > either, > > since it's buried behind the front panel of the > > chassis and has the big control connector on it. > > > > Bob M. > > ======= > > --- Milt <[EMAIL PROTECTED]<mailto:mengle%40pa.net>> > wrote: > > > > > Bob, > > > > > > The info you need is contained in FMR-1735A-1 > > dated > > > June 1996 > > > > > > The Audio squelch board in the radio is > replaced > > > with HLN5342ESP01 > > > > > > From Pin 9 on the front connector (the former > busy > > > light line) on the > > > interconnect board, the signal feeds through > > JU1510 > > > to pin 12 of J21 the > > > audio board connector. JU1509 and 1511 are > open, > > > JU1512 is in. > > > > > > J21 pin 12 is the pin 2 input of U1103. JU1202 > is > > > out. > > > > > > IIRC busy light is not used on A7 heads with > the > > > remote squelch control > > > option. > > > > > > It's possible that you have a missmatch > between > > the > > > head and audio squelch > > > board. > > > > > > Milt > > > N3LTQ > > > > > > ----- Original Message ----- > > > From: "Bob M." > <[EMAIL PROTECTED]<mailto:msf5kguru%40yahoo.com>> > > > To: > <[email protected]<mailto:Repeater-Builder%40yahoogroups.com>> > > > Sent: Monday, February 04, 2008 6:26 AM > > > Subject: Re: [Repeater-Builder] Re: Low-band > > > MaraTrac Squelch Pots > > > > > > > > > > Thanks to the people who posted the link. I > had > > > seen > > > > that page earlier but didn't follow the > signal > > off > > > the > > > > board. > > > > > > > > The pot in the control head seems to have > its > > arm > > > and > > > > one end connected to ground. The other end > goes > > > > through some resistors before leaving the > > control > > > > head. I can see the effect of turning the > pot > > down > > > at > > > > pin 9 of the control cable; it varies from > about > > > 3-5 > > > > kOhms. I thought it was just a DC signal or > just > > a > > > > varying resistance to ground. > > > > > > > > The schematic posted doesn't show the wiring > > from > > > the > > > > audio board out to the pot on the control > head. > > > I'm > > > > guessing that the signal coming into the > squelch > > > pot > > > > on the audio board is detected audio, since > it > > > then > > > > feeds the internal squelch pot which sets > the > > gain > > > and > > > > threshold of the squelch circuit. > > > > > > > > I'll have to rethink and evaluate this new > > > > information. > > > > > > > > Bob M. > > > > ====== > > > > --- sgreact47 > <[EMAIL PROTECTED]<mailto:echocomms%40hotmail.com>> > wrote: > > > > > > > >> Bob, > > > >> > > > >> Look here for the modified audio board. > > > >> > > > >> > http://www.batlabs.com/images/marsqsch.jpg<http://www.batlabs.com/images/marsqsch.jpg> > > > >> > > > >> The squelch control circuit is there, uses > the > > > >> Micor, MSF, high > > > >> speed squelch. > > > >> > > > >> "Bob M." <[EMAIL PROTECTED]> wrote: > > > >> > > > > >> > I'm working on a 42-50 MHz MaraTrac with > the > > A7 > > > >> > advanced head that has a squelch pot on > it. > > The > > > >> > squelch is open all the time, and neither > the > > > >> control > > > >> > head pot or the pot inside the radio will > > close > > > >> the > > > >> > squelch. ____________________________________________________________________________________ Looking for last minute shopping deals? 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