Motorola Maratrac Question

[realgeo]

Good evening, everyone!

Okay - here's a good question for all of those who have experience with the older Maratrac radios, especially those that have attached PAC-RT units! :*)

Is there some sort of fuse in the control head, which might be blown due to unwise connecting and disconnecting of radio control cables when power was applied?

You know where I'm going with this! I happened to be working in my cruiser tonight and was doing some re-wiring of the Maratrac and PAC-RT cables. What I forgot to investigate was whether or not DC power was applied prior to doing my work. D'OH!

The control head lit-up and responded to button presses prior to the exercise, however does not at this point! The PAC-RT does emit the "tone" on the VHF channel when activated, however, it appears that no radio traffic is being passed between the Maratrac and PAC-RT.

I know this isn't a technical forum for Motorola radios, but thought I might toss the question out anyway, considering the breadth of knowledge I know exists here!

Thanks and 73's

 

[rcvmo]

I'm still trying to get used to the early morning shift here, so i'll see if I can help you out here. More coffee pleeez!!
No sorry, no fuse. Check all the associated external fuses. Sounds like a circuit trace maybe opended in the CH. Yikes! Can you get another control head to test?
Yes............working with radio and other comms equipment with the power on can be hazzardous to your radio and your health.

Good luck.
rcvmo

 

[W0JJK]

Does the Oragne and Red Light on the head light up?

If so I would would check the main power fuse.

If not, check the two fuses first. They are 3 amp fueses.

 

[obijohn]

Hey Geo...Is that a low band radio with the squelch control on the ch?

I could loan ya a regular head, but I don't have one with the squelch knob.

P.S. I should have a schematic of the advanced control head.

 

[realgeo]

Hey Geo...Is that a low band radio with the squelch control on the ch?

I could loan ya a regular head, but I don't have one with the squelch knob.

P.S. I should have a schematic of the advanced control head.

Howdy John and everyone!

Steven - thanks for the suggestion! I believe I need to trace out some fuses!

John - nope, no squelch control on my control head - it's a "normal" control head, and yes it's on low-band in the 36-42 split!

Let me do some tracing on fuse integrity - if the fuses are good, then I'd like to explore a different control head!

Thanks to all for the suggestions! I do appreciate it!

73's

 

[NeFire242]

This wouldn't be the Plattsmouth cruiser that was sitting in Murray would it?

 

[realgeo]

This wouldn't be the Plattsmouth cruiser that was sitting in Murray would it?

Nope!

73's

 

[SLWilson]

Control Head....

Good evening, everyone!

Okay - here's a good question for all of those who have experience with the older Maratrac radios, especially those that have attached PAC-RT units! :*)

Is there some sort of fuse in the control head, which might be blown due to unwise connecting and disconnecting of radio control cables when power was applied?

You know where I'm going with this! I happened to be working in my cruiser tonight and was doing some re-wiring of the Maratrac and PAC-RT cables. What I forgot to investigate was whether or not DC power was applied prior to doing my work. D'OH!

The control head lit-up and responded to button presses prior to the exercise, however does not at this point! The PAC-RT does emit the "tone" on the VHF channel when activated, however, it appears that no radio traffic is being passed between the Maratrac and PAC-RT.

I know this isn't a technical forum for Motorola radios, but thought I might toss the question out anyway, considering the breadth of knowledge I know exists here!

Thanks and 73's

There SHOULD be a 30 Amp fuse for the trunk unit. It SHOULD have a separate fuse holder up under the hood (very close to the battery) and it is a round glass type fuse.

There is a small (I don't recall the amp size) glass fuse for the control hed (there MAY be two fuses for the head) There is a green wire that powers up the head and an orange wire that is switched (if the head is wired hot - for continuous ON of the radio, chances are, there is only one fuse and the orange & green wires are tied together) that will let the head light up EVEN IF the main 30 Amp fuse is blown.....

PLUS, depnding on the style PAC you have (old Motorola or newer modified small after mkt unit) IT too will be fused....

Let us know what you found out about it!!!! Thanks,

Steve/Gallia 911

 

[obijohn]

I almost forgot to mention it, Geo. If you had the cable end off that connects to the radio end of the cable (The large connector) verify that when you re-attached it to the radio drawer that you didn't catch a pin at an angle, and bend it over.

I have seen this happen twice! If you checked the control head fuses on the green and orange wires and they are not blown, then check out the radio-end connector.

 

[wb0qqk]

Hi George,
I don't know if it would be of much help, but I found a Maratrac manual in my
pile of books. It came from OPD back in July 1989 and of course it's UHF, but
it has the wiring diagrams, board and component layouts for the HHCH, standard
clamshell and advanced control heads with VIP. My guess is that the head and
cables wil be pretty much the same between drawers regardless of band.
73,
Frank - WB0QQK

 

[realgeo]

Howdy, everyone!

Thanks to one and all for the suggestions and support! What a SUPERB example of people helping one another! A shining example of the spirit of Amateur Radio.

I'll have more time this weekend, once I get this class done, and will do some fuse-tracking. By Sunday, I should know more and will post my results!

Thanks, again!

73's