Motorola Astro Spectra Railroad

[800trashman]

I have searched extensively, and found nada, please forgive me if I am searching the wrong thing. I have a Astro Spectra RR radio, and looking to use it indoors via the 13.8, with a Astron power unit. As you know these units have the 72v plug on the unit. I am not good at wiring at all, and looking to see if there is a converter that is made somewhere that will allow me to plug into that plug on the radio and connect to my Astron power unit? Any help is much appreciated!

 

[Josh]

The connector is four pin...two are used for 70 VDC and the other two are for 12v.

 

[com501]

Google the pin out and get the polarity correct the first time. Don't blow up an irreplaceble radio.

 

[800trashman]

Google the pin out and get the polarity correct the first time. Don't blow up an irreplaceble radio.

Exactly!, That is why I was looking for a pre-made unit, that I could not screw up!! I have this from Batlabs, but is greek to me...

(The pinouts of the connectors on the radio go like this:

Power connector:

A --- +72 volts
B --- -13.8 volts
C --- - 72 volts
D --- +13.8 volts
Use only A and C for railroad 72 volt (nominal 64V supply) power, or B and D for 13.8 volt (nominal 12V supply). The 72 volt supply floats; the 13.8 volt supply is negative ground.)

Is there a connector sold somewhere that would let me just plug into the wall - or my power unit?

 

[com501]

That connector is a pretty standard Amphenol/Cannon style connector. You can get them from Mouser or Newark electronics. The Motorola manual (if you can find one) may have a parts breakdown showing the manufacturer part number. Batlabs is a good resource and if you do not have the rear connector, someone there may be able to offer you a resolution.

The rear connector (if you have it) will have the pin numbers somewhere on the housing, and you can de-pin the connector and swap the wires to the correct pins.

 

[800trashman]

So if B is my negative, and D is my positive on the 13.8, any reason why I cant use the Red and Black wires from my Astron power unit and somehow couple them with the Amphenol/Cannon style connector and get power that way?

 

[com501]

No problem at all. I would try to source that connector, it makes it a LOT easier.

 

[com501]

Remember that Railroad Spectra are FLOATING GROUND. Make sure you wire both the positive and negative leads to the connector and not chassis.

 

[com501]

Batlabs was a source for the power connector, read their site.

 

[Josh]

Whether you use 70vdc or 12vdc, both are filtered and sent through a DC DC converter for isolation. It's the radio that's grounded, not the power source.

 

[800trashman]

Whether you use 70vdc or 12vdc, both are filtered and sent through a DC DC converter for isolation. It's the radio that's grounded, not the power source.

So if I use my Astron power unit (thus giving me an on off switch), add the Amphenol connector with B & D ports connected to red and black , and not worry about adding a ground wire?

 

[800trashman]

Can anyone advise what the antenna connector is on the Astro Spectra RR radio? Is it the standard mini uhf? Thanks

 

[kg6nlw]

It is a standard PL-259 connector for the antenna.

Regards,

-Frank C.

 

[ElroyJetson]

No it's not. Every Motorola mobile radio from the Maxtrac line going forward uses a MINI UHF connector.

Which I hate...but at least it fits through a small hole.

Does this look like a PL-259 to ANYBODY?

 

[12dbsinad]

Which I hate...

You're not alone. But it does generate a lot of service calls for radio issues only to find a loose mini UHF..
I would much rather see them use something like a TNC like GE used on some of their radios. At least it has a gasket to tighten against and is much less subject to loosening.

Does this look like a PL-259 to ANYBODY?

It looks like a F connector. I have ran across many F connectors threaded on a spectra and the like. Threaded on with a pair of pliers of course.

 

[mancow]

You're not alone. But it does generate a lot of service calls for radio issues only to find a loose mini UHF..
I would much rather see them use something like a TNC like GE used on some of their radios. At least it has a gasket to tighten against and is much less subject to loosening.



It looks like a F connector. I have ran across many F connectors threaded on a spectra and the like. Threaded on with a pair of pliers of course.

It's a mini-uhf.

 

[Josh]

The railroad version, if it's the clean-cab model will have a standard PL259 connection, but from what it sounds like, the original poster does not have the actual radio in their possession.

 

[12dbsinad]

It's a mini-uhf.

Yes, I am well aware. My comment was pure sarcasm given what I have seen done in the communications industry.

 

[800trashman]

The railroad version, if it's the clean-cab model will have a standard PL259 connection, but from what it sounds like, the original poster does not have the actual radio in their possession.

This looks like a mini uhf to me, no?

 

[jim202]

That my friend is what many people call an SO-239. It's the female connector that mates with a PL-259. You use a standard PL-259 connector on it.