Batboard

Upgrading a Gr300 repeater,

So my question is , If I upgrade to CDM750s are the plugs and pins going to be the same or will it require modification? I realize the CDM will fit a little differently.

Thanks, from what I can see everything looks the same going to the RICK.

just make sure you program the CDMs accordingly

just did the same with some PM400s

customer did not want to listen to me about heat dissipation

they will be back soon

Yes, all the plugs will fit. And as escomm said, better program the accy ports correctly. But, I don't see how you'll get them to fit without some serious modification to the housing.

According to the schematic, pins 15 & 16 on the Basic Controller TX radio jack are connected internally. Wouldn't that connect SPK+ to RSSI on a CDM?

Hello:
Are you by chance upgrading the GR300 repeater from wide band to narrow band ?
If so the GM300 was made in narrow band from the factory and I do have some if youd prefer to use the the GM300 radio.
The GM300 from Motorola would do the normal freqs at 12.5 narrow band but I don't think they do the new in the middle freqs like 464.1250 but will do 464.2500 MHz at narrow band.
Unless you shift key enter it then tune maybe - Havent tried that.
But if you had a licensed freq on wide going to narrow band now then the original gm300 narrow band mobiles will work.
Satelite

jackhackett wrote:According to the schematic, pins 15 & 16 on the Basic Controller TX radio jack are connected internally. Wouldn't that connect SPK+ to RSSI on a CDM?

Oh yeah. I see what you mean. That is the one difference between CDM's and Maxtrac/GM series. The CDM has a full time live speaker. No jumper necessary. If present, it can be removed.

escomm wrote:customer did not want to listen to me about heat dissipation

they will be back soon

That is why we use only the best German fans. frozencpu.com

Bill_G wrote:But, I don't see how you'll get them to fit without some serious modification to the housing.

Flip the GR300 housing and get a GR500. No shortage of hams who will pay top Ebay dollar for a GR300 housing.

I would pull out the pin 15 wire on the accessory plug cable for the TX radio and tape it off so it doesn't short to anything, that should solve the speaker wiring difference. On the RX radio, pin 15 is routed to the ACC jack on the controller which if I recall correctly doesn't normally have anything plugged into it. If there is a plug there with 15 & 16 jumped you'd have to remove that jumper as well.