Batboard

Good day everyone. I have been a frequent visitor to the site but now I have a question that I could not find the answer to from a search. I purchased a used Astro about a week ago. To test the unit, I powered it up using a jumper going to the ignition sensor. After determining that the radio worked, I purchased the 15 pin cable and wired in the ignition and speaker wires.

I powered the unit on with no problem, and sound from speaker was good. Plugging in an antenna, I keyed up the unit and it went out. I now cannot get it to power on, stopping at the "light up" phase of the XMIT & BUSY lights. Nothing is coming up on the display. I have rechecked connections with everything looking good. Unplugged power to the unit and left in for a few minutes. Each time I attempt to power back on I get the same results.

Any suggestions would be helpful as I would rather have burnt up my money in Vegas rather than on burning up a radio.

Bob

You didn't mention anything about applying power to the 2 pin connector on the back of the radio. This
connector supplies power to the transmitter PA. If you didn't have power applied to this 2 pin connector,
you probably blew the internal fuse from the ignition control line on the DB15 connector to the rest of the radio.

With this fuse blown, the radio will not power up without the rear 2 pin connector having 12 volts on it.

If you don't have a heavy power cable and connector, you can go to your local auto store and obtain
a 2 pin trailer wire connector and wires. It is not as heavy as the normal Motorola power cable, but
if you don't do much talking, it will work just fine.

I could be wrong, but my money is on the internal fuse got blown when you tried to TX and no power
on the 2 pin connector.

Jim

Bvankl wrote:Good day everyone. I have been a frequent visitor to the site but now I have a question that I could not find the answer to from a search. I purchased a used Astro about a week ago. To test the unit, I powered it up using a jumper going to the ignition sensor. After determining that the radio worked, I purchased the 15 pin cable and wired in the ignition and speaker wires.

I powered the unit on with no problem, and sound from speaker was good. Plugging in an antenna, I keyed up the unit and it went out. I now cannot get it to power on, stopping at the "light up" phase of the XMIT & BUSY lights. Nothing is coming up on the display. I have rechecked connections with everything looking good. Unplugged power to the unit and left in for a few minutes. Each time I attempt to power back on I get the same results.

Any suggestions would be helpful as I would rather have burnt up my money in Vegas rather than on burning up a radio.

Bob

Sorry, I forgot to mention that the 2 pin connector was also powered up using a 10 amp power supply. If the internal fuse is blown, is that user changeable and is there a way to physically look at the fuse to determine if it is the problem?

Ok, Ill try to send results in the order that they were sent:

1. Pins were jumpered to close the emergency switch prior to problem. Radio did have succesful power up prior to being "keyed up".

2. Tried disconnected all external (antenna, speaker, mic) with no changes.

3. I do not have any other head to try using.

4. No unusual odors are coming from the unit.

My technical skills are sketchy at best to open the radio up. If a fuse could be bad and easy to get to, I would feel comfortable opening it up for a quick look.

This originally was a project to help save some money for a smaller agency who is on a P25 system. I hate to put much more money into this or to send it off for a repair job. Is there any market for one of these on a "tech special" basis. It was originally on the Ohio MARCS system.

Still open to any suggestions. Thanks already for the help.

Yep, checked that first. No luck. I will take a look to see if the diode is the source of the confusion.

Bob

Ok, Diode checked and working properly by a meter. On a quick look of the circuits from the access doors finds no unusual discolorations or marks. Any other suggestions?

OK, lets go back to the start of the problem here.

You should have a jumper from pin 2 (emergency) to pin 8 which is ground.

Speaker wires are pins 6 and 7. Make sure there is no ground on either wire.

The ignition sense wire +12 volts is on pin 5.

Check the high current power feed to the rear of the radio, 2 pins. Make sure you don't
have a poor fuse connection. This feed must be there to get the radio to power up. If
when you tried to key the radio up and this feed went low, the radio would go into a
computer reset and start all over again.

Another problem that can cause issues, is poor connections between the boards in the
radio. The fix for this would be to take the radio apart. This means pulling the boards
apart and re-seating them a couple of time. This inter board connection through the
multi pin connector in the middle of the boards has been know to cause all sorts of
problems with proper radio functioning.

Taking the radio apart is not that hard. You just need to have the correct torx drivers.
There is a metal clip over the audio transistors at the rear of the radio that needs to be
pulled off. When you put it back together, just slip the clip back on. You will also need to
pull the control head off and pull the adapter out of the front. In the rear is the small gray
connector coming from the PA.

Have fun.

Jim

Not sure on the model\flascode,but could the radio have a private trunking system programmed in it,and it attemped to affiliate ?

What were you keying up on ?

If it did,It may have been bricked.Usually gives you the same symptoms,where radio powers up and all the lights come on,but it doesn't work.