Just Bought a MaxTrac, confused about plug and internal chip.

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fireball517
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Just Bought a MaxTrac, confused about plug and internal chip.

Post by fireball517 »

I just bought a maxtrac but cannot get it to come on so I opened it up and noticed I had wires running to this board Image and a connector coming out of the back Image, does anybody know what this board is for and why I can't turn on this radio? Are there pins on the back I need to jump for power?

Model:D44MJA7JA5AK
16 Pins on the back.
Type:MJUA
RadioSouth
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by RadioSouth »

Looks like an add on board, with the M branded IC it could be a QCII decode board or could be an aftermarket board that just happens to use a Moto IC. If the radio was set up for ignition sense, yes you need to apply power to a pin on the 16 pin connector, the pinout is shown on the Main Batlabs site.
Satelite
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by Satelite »

Hello
Just an observation= The add on bd has a white sticker marked 025 which happens tp be a digital private line code . ?????
And I'm reaching back many years when I repaired the maxtracs here but his model number he posted indicates its a maxtrac 300 series mobile with the high tier HLN9313 16 pin logic bd.
If that's the case then I recall the maxtrac 300 already did Quick call II as standard feature just had to program it in.
I know for a fact the maxtrac 300 decoded on receive but think unless I'm wrong the radio also would encode on transmit a QCII tone.
I wish I had my maxtrac 300 programming book now to confirm but maybe some one here remembers and will answer that question.
So if that's the case then there wouldn't be a need for the add on Quick Call II bd unless the codes were non standard and required a special bd to do the non standard.
Or previous repair person wasn't aware the maxtrac 300 did QCII decode and programmed a channel csq then added the QCII Board to do it ????
My first thought with just a glance before looking much at the bd was a scrambler bd was added for privacy but I'm not so sure but it does have a tubular crystal on the board so ????
Just rambling here so make what you think of it as confusing info.
And yes I bet previous postee RadioSouth is correct radios set up for ignition sense so apply positive power as normal plus jumper a wire from pos input to rear pin 16 and see if it doesn't power up.
If it does check programming for any channel set for CSQ or QCII and if tx is clear or scrambled.
That wil give you a pretty good idea what the bd is then.
Satelite
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jackhackett
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by jackhackett »

Appears to be a Selectone ST-20 inversion scrambler.

http://www.com-spec.com/selectone/manual/st020man.pdf
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jackhackett
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by jackhackett »

Satelite wrote: And yes I bet previous postee RadioSouth is correct radios set up for ignition sense so apply positive power as normal plus jumper a wire from pos input to rear pin 16 and see if it doesn't power up.
Do NOT connect power to pin 16 on the accessory connector. Ignition sense input on a Maxtrac 16 pin connector is pin 10.
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SteveC0625
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What radios do you own?: CDM's, CP's, CM's, and more

Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by SteveC0625 »

Satelite wrote:And yes I bet previous postee RadioSouth is correct radios set up for ignition sense so apply positive power as normal plus jumper a wire from pos input to rear pin 16 and see if it doesn't power up.
Pin 16 in that radio is the + half of the isolated loudspeaker output. Connecting +12vdc to it will likely blow out the audio amp.

As jack said, Pin 10 is ignition sense.
Satelite
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by Satelite »

Hello:
OOOOPS wow glad u guys corrected me.
Didn't realize I had typed that as such .
My mind was on 16 pin logic bds 16 pins and wow cant believe I said it but yes pin 10 of the 16 pin logic bd pins not pin 16.
MY BAD
Normally myself I just resolder a 1 or 2 amp fuse back in on the logic bd at JU801 .
The fuse is normally a green pico type and its on logic bds top side behind the 16 pin connector and further down below speaker J10 plug then below capacitor C451 and finally below it you should see a row of 4 components ressistors with the 3rd from right not a resistor but looks similar and should be green color.
Previous tech may have unsoldered it or when 12 v positive power is hooked up at logic bds pin 10 when installed normally blows the JU801 fuse so its ignition sense operated by applying 12v plus power on pin 10.
So you could open up radio check JU801 fuse to see if good or carefully with radio in on position and 12 volts jumper the green JU801 fuse to see if radio powers up.
If so replace fuse with 1 or 2 amp fuse.
If you cant find a green pico type fuse you could solder wire leads from JU801 and solder a fast blow glass fuse inline.
Just make sure fuse is insulated in a way it wont short out on anything.
MODS COULD YOU EDIT MY POST ABOVE SO NO ONE TRIES IT AND SMOKES THERE RADIO> IM OK WITH OTHERS KNOWING I OOOPED BUT WOULD REALLY LIKE YOU TO ADD TO IT AND CORRECT THE BAD INFO FROM 16 TO PIN 10 INSTEAD.
I would but cant edit it to save someone in future .
Satelite
fireball517
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by fireball517 »

So would running a jumper between the two wires on the connector activate voice inversion? I have no use for it but it is nice to know what it is for, thanks so much all!!
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jackhackett
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by jackhackett »

It's hard to say what the connector is for without seeing what it's connected to. It could be for an external switch to turn the encryption on, or it could be for something else.
Satelite
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by Satelite »

Hello:
It was an option to turn on turn off the inversion scrambler in a maxtrac by double tapping the monitor button on radio when on.
Obviously 1 tap turned private line off as in monitor mode and second tap would turn pl back on but also turned on scrambler.
My first gut feeling also as jackhackett said was it might have been a on off connector for the scrambler.
Id follow the two wires back into radio and see where they hook up tell us and maybe we could tell you better.
I do have the schematics to that scrambler so could look it up.
If it goes to a wire or two to the inversion scramblers bd tell us the color code of the wire its connected to.
If youd rather have just a maxtrac 300 as it is normal id be willing to trade you radios as I do have these out in the field with users yet that were not affected by the narrow band ruling and their using the radios with inversion scramblers (Ham Band)
Thank you
Satelite
bitcohen
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by bitcohen »

Hello all !
I have a maxtrac 800 that I am trying to get working... When it is powered on it makes to tones (I thought it could be because it was not connecting to control freq) but I used a friends programming software to try and access and change the control freq but when I run the software I get a power on failure from the software and will not connect to the radio. Anyone have any ideas?
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jackhackett
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Re: Just Bought a MaxTrac, confused about plug and internal chip.

Post by jackhackett »

bitcohen wrote:Hello all !
I have a maxtrac 800 that I am trying to get working... When it is powered on it makes to tones (I thought it could be because it was not connecting to control freq) but I used a friends programming software to try and access and change the control freq but when I run the software I get a power on failure from the software and will not connect to the radio. Anyone have any ideas?
First, this should have been started as a new topic as it has little to do with the previous discussion. Maybe a mod can move it to it's own topic.
Second, it will help us to know what model number the radio is, which software you tried to read the radio with (Maxtracs use different software for conventional and trunking models) I believe it shows the part number of the RSS on the screen when you first run it but it's been a while so I can't say for sure. Also what type of computer, OS, RIB, and cable are you using?
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