Batboard

No it's another "how do I..." post.

My question/problem is this: For the longest time, about a year or so now, my mobile Maratrac has worked fine. Recently I moved it from one portion of the van to another. Same wiring, different location. I'm using 8 gauge wire between the radio and the Anderson PowerPole Multi-coupler (for lack of a better word) with proper fuses inline (30a on +/- lines), and then the Maxi Fuse connecter which has 80a fuses on the +/- lines as well.

Now when I go to turn on the radio, nothing. When I plugged the radio back in there was a tick like sound at the PowerPole Multi-coupler, the Maratrac was the only radio on the bar at the time. I have a second Maratrac cable that I did hook up to the radio and control head and it works fine, through the same power setup, so I've narrowed it down to the cable.

Anyone have any ideas?

Regards,

-Frank C.

fchrist16 wrote:No it's another "how do I..." post.

My question/problem is this: For the longest time, about a year or so now, my mobile Maratrac has worked fine. Recently I moved it from one portion of the van to another. Same wiring, different location. I'm using 8 gauge wire between the radio and the Anderson PowerPole Multi-coupler (for lack of a better word) with proper fuses inline (30a on +/- lines), and then the Maxi Fuse connecter which has 80a fuses on the +/- lines as well.

Now when I go to turn on the radio, nothing. When I plugged the radio back in there was a tick like sound at the PowerPole Multi-coupler, the Maratrac was the only radio on the bar at the time. I have a second Maratrac cable that I did hook up to the radio and control head and it works fine, through the same power setup, so I've narrowed it down to the cable.

Anyone have any ideas?

Regards,

-Frank C.

Get out your volt meter and find where your missing the voltage for the radio. You should have an orange and green wire for the control head. These both need to have +12 volts to turn the radio on. Normally you feed these from the ignition switch feed. Don't forget that the high current red wire also needs +12 volts for the radio to come on. There is the large black wire from the radio that needs to go to chassis ground.

Jim

+1

The voltmeter is your friend.

fchrist16 wrote: which has 80a fuses on the +/- lines as well.

Frank,

You should NOT fuse the black power lead. It should go to ground/frame of the vehicle near the radio.

The Red lead AND the small green lead must go direct to the battery.
The small Orange lead can go to the IGN switch or battery.

Fuse ratings:

Main RED power lead 30 amps
Green lead % amps
Orange lead 1 amp

Forgot to mention that...Blame it on being tired!

Orange/Green & Red all go to the same source.

Voltmeter checks the radio out as getting power inside the "chasis" and at the end of the cable. So all is good in power land, minus the radio starting up...

Regards,

-Frank C.

Have you tried measuring the resistance of each cable lead? Sometimes that's a better indicator than measuring voltage.

I believe you need to have the voltage on the red and green leads be very close, some high resistance in a cable could be throwing that off.

Bear in mind that after being disconnected for a while, the MaraTrac power supply section has a pretty good inrush current as the capacitors charge when the power is reconnected, and that "tick" you heard is actually normal when the juice arcs across the connections as the final current-bearing surfaces approach each other and there's an arc. If you're hearing an arc anywhere other than where you're closing a connection, there are some bad connections somewhere. Look on the contact surfaces of the connectors and at the fuse connections for black and/or burn spots, or evidence of movement that has worn the plating off the contact surfaces. Check for corrosion also. Mechanical and corrosion defects will definitely give you the symptoms you describe, and the sound you heard may be an indication of arcing in more than one spot. That alone is enough to warrant a good connector inspection, but if your real problem seems to be the control cable, check the control head end.

Check the control head end of the control cable for a broken connector body by holding the body of the connector and wiggling the portion that fits into the control head connector. The black plastic gets brittle with age and being sprayed with the wrong kinds of contact cleaners. The break will show up in a bright light as you will be able to see the gold color of the female pins showing through the crack in the black plastic, and an obvious line of separation will be visible around the portion of the connector that fits into the control head connector. The pins won't seat properly and you'll get various unpredictable symptoms ranging from minor to catastrophic. This could easily include having all the voltages in the right places, but no communicating between the head and the radio.

As an aside and if the control cable isn't the culprit, I've seen a no-go problem far more than once with the Anderson Power Poles in the "ham radio" size when carrying a good bit of current, and a thorough check both with the multimeter and visual inspection of the connectors is the ticket for sure. Truthfully, they are barely adequate for intermittent 30 amps to begin with in that size, and a temp check while transmitting for 10 seconds or more will reveal that.

Not saying this applies to every situation, and frankly, your mileage may vary, but I've found those devices to be far less than reliable in high current applications where there can be repeated unplugging and plugging in or vibration movement in the connector, and a MaraTrac ain't a low current unit. Power Poles in that size don't seem to tolerate vibration or movement while dealing with currents over about 10 or 12 amps, and when you pass 26-30 amps through them and introduce mobile vibration and jounce or frequent plug/unplug cycles, the connector will eventually fail. They do seem to be OK with lower currents, but it seems the more vibration, the less the current capacity over time. In a nice, smooth-riding vehicle that never sees frost-boiled pavement, pot holes, and manhole cover dips, they will most likely give a longer life, but this ain't a perfect infrastructure world. This contact problem has NOT been a problem with the larger sizes of the Power Poles, BTW, and if you upgrade, your connector mileage may increase. As for me, I avoid those things like poisonous snakes.

jackhackett wrote:Have you tried measuring the resistance of each cable lead? Sometimes that's a better indicator than measuring voltage.

I believe you need to have the voltage on the red and green leads be very close, some high resistance in a cable could be throwing that off.

No I haven't measured that yet. Just the Pos/Neg lines.

wx4cbh wrote:Bear in mind that after being disconnected for a while, the MaraTrac power supply section has a pretty good inrush current as the capacitors charge when the power is reconnected, and that "tick" you heard is actually normal when the juice arcs across the connections as the final current-bearing surfaces approach each other and there's an arc.

Sounds like it maybe this...

wx4cbh wrote:As an aside and if the control cable isn't the culprit, I've seen a no-go problem far more than once with the Anderson Power Poles in the "ham radio" size when carrying a good bit of current, and a thorough check both with the multimeter and visual inspection of the connectors is the ticket for sure. Truthfully, they are barely adequate for intermittent 30 amps to begin with in that size, and a temp check while transmitting for 10 seconds or more will reveal that.

Not saying this applies to every situation, and frankly, your mileage may vary, but I've found those devices to be far less than reliable in high current applications where there can be repeated unplugging and plugging in or vibration movement in the connector, and a MaraTrac ain't a low current unit. Power Poles in that size don't seem to tolerate vibration or movement while dealing with currents over about 10 or 12 amps, and when you pass 26-30 amps through them and introduce mobile vibration and jounce or frequent plug/unplug cycles, the connector will eventually fail. They do seem to be OK with lower currents, but it seems the more vibration, the less the current capacity over time. In a nice, smooth-riding vehicle that never sees frost-boiled pavement, pot holes, and manhole cover dips, they will most likely give a longer life, but this ain't a perfect infrastructure world. This contact problem has NOT been a problem with the larger sizes of the Power Poles, BTW, and if you upgrade, your connector mileage may increase. As for me, I avoid those things like poisonous snakes.

Those big fat Anderson PowerPoles are not good enough eh? Good to know. Sadly though all my equipment is equipped with them as I was tired of having to constantly change "O" Rings out. Apparently there was enough stress on the "O" Rings, and often enough, that they snapped about 3 months into their lifespan! I've yet to have a problem like that with the PowerPoles!

I'm taking a break tomorrow from the cable, but if anyone has any other ideas I'm more than willing to try them out!

Regards,

-Frank C.

fchrist16 wrote:

jackhackett wrote:Have you tried measuring the resistance of each cable lead? Sometimes that's a better indicator than measuring voltage.

I believe you need to have the voltage on the red and green leads be very close, some high resistance in a cable could be throwing that off.

No I haven't measured that yet. Just the Pos/Neg lines.

That's pretty much what I meant... measure the resistance of the power, ground and ignition leads to make sure there's not a bad splice or poor contact on a fuse or something.

jackhackett wrote:That's pretty much what I meant... measure the resistance of the power, ground and ignition leads to make sure there's not a bad splice or poor contact on a fuse or something.

Did that and everything "checks out" ok. Not sure where else to look now...

Regards,

-Frank C.

fchrist16 wrote:

jackhackett wrote:That's pretty much what I meant... measure the resistance of the power, ground and ignition leads to make sure there's not a bad splice or poor contact on a fuse or something.

Did that and everything "checks out" ok. Not sure where else to look now...

Regards,

-Frank C.

OK, lets start over and begin the old voltage check again. Turn on the control head switch on the bottom of the control head.

Take your volt meter and find the last point on the 2 control head power wires (orange and green) and measure the voltage. If you have a real sharp point on your meter probe, try pushing it through the insulation near the control head. Make sure you have the correct battery voltage there (+13.8 or so with the engine running). If not, then trouble shoot the wire with the low voltage. Maybe a corroded splice or fuse connection.

Do the same thing on the heavy current red wire. Make sure you have normal supply voltage right at the radio.

Next take your volt meter on a low DC scale and measure from the antenna connector to the frame ground of the vehicle and see if you have any voltage. You could have a poor or bad ground on the heavy black wire from the radio to the frame ground. You need a good ground to even power up the radio.

If you haven't found anything by now, then you had better start using your Ohm meter to check out several of the power control wires in the control cable. There are not that many that need to be checked. Look at the grounds, sw B+, forget what the battery voltage wire is called.

Jim

I concur with jack and jim202 about the voltmeter check. If you have checked the control cable for continuity as suggested, here is a quickie check for basic voltages through the green and orange leads, and through the control cable to the radio end. Realize that you are not going to see the loaded voltages, but it should give you some idea of whether things are somewhat OK as far as basic voltages go. Note that with MaraTracs, voltage on the large red wire and the orange wire isn't necessary to get the radio to turn on and receive as long as the large Black wire is grounded. The large red wire supplies the transmitter PA and the orange wire controls the PTT functions in conjunction with the RSS settings.

Turn off the control head power switch. Remove the head end of the control cable and look for the tiny numbers on the head side of the plastic control cable connector housing. If your voltmeter leads have points that you can reach the pins inside the connector, look for the green lead voltage at PIN 47, and the orange lead voltage at PIN 15. If the leads are not small enough, insert a short, small diameter pin or wire into the holes so you can measure the voltages. That voltage goes through the control head and through the control cable to the large connector on the radio end.

Plug the control cable back into the control head. Unplug the radio end of the cable and check the control cable's connector pin numbers listed below.

PIN 4 B+ voltage < green lead voltage should be here when the control head On/Off switch is ON and it should be very, very close to the voltage that's on PIN 19.
PIN 17 A- Ground < from large Black wire
PIN 19 A+ Battery < from large Red Wire
PIN 13 On/Off < should change states with the control head On/Off switch.

wx4cbh wrote:I concur with jack and jim202 about the voltmeter check. If you have checked the control cable for continuity as suggested, here is a quickie check for basic voltages through the green and orange leads, and through the control cable to the radio end. Realize that you are not going to see the loaded voltages, but it should give you some idea of whether things are somewhat OK as far as basic voltages go. Note that with MaraTracs, voltage on the large red wire and the orange wire isn't necessary to get the radio to turn on and receive as long as the large Black wire is grounded. The large red wire supplies the transmitter PA and the orange wire controls the PTT functions in conjunction with the RSS settings.

Turn off the control head power switch. Remove the head end of the control cable and look for the tiny numbers on the head side of the plastic control cable connector housing. If your voltmeter leads have points that you can reach the pins inside the connector, look for the green lead voltage at PIN 47, and the orange lead voltage at PIN 15. If the leads are not small enough, insert a short, small diameter pin or wire into the holes so you can measure the voltages. That voltage goes through the control head and through the control cable to the large connector on the radio end.

Plug the control cable back into the control head. Unplug the radio end of the cable and check the control cable's connector pin numbers listed below.

PIN 4 B+ voltage < green lead voltage should be here when the control head On/Off switch is ON and it should be very, very close to the voltage that's on PIN 19.
PIN 17 A- Ground < from large Black wire
PIN 19 A+ Battery < from large Red Wire
PIN 13 On/Off < should change states with the control head On/Off switch.

Now that I've rested and am coming back to this fresh...Used my voltmeter and both ends of the control cable check out as "OK". Any other ideas??

Regards,

-Frank C.

Well, we've kinda exhausted the diagnose-from-a-distance portfolio. Now it's at a get-the-manual-out-and-check-the-test-points-in-the-radio stage. The logic chart is pretty good at getting you to the problem area, and since a MaraTrac is a good ol' discrete component radio, repairs are not so hard as long as it doesn't require a chip replacement, and that ain't too bad if you have the gear.

Got a manual laying around? I don't have one...

Regards,

-Frank C.

In the original post he said the radio works with another cable.... so that *should* rule out a radio or control head problem.

Jack, you are so right, but I kept going because he kept going. And too, the interconnect info is good for all three versions and may be useful to others reading the post. As to a manual, the only one I have is a low band version.

That's fine as this is the low-band Maratrac!

Regards,

-Frank C.

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