CP200d and fuse

Moderator: Queue Moderator

Post Reply
User avatar
arlojanis
Posts: 1009
Joined: Mon Jan 28, 2002 4:00 pm

CP200d and fuse

Post by arlojanis »

I have a CP200d VHF analog (in service for 3 years) that had a blown fuse. I replaced the fuse and radio was good for 30 minutes. I switched radio off and let it sit overnight. Next morning the fuse was blown again. What is the problem?
"The world runs on radio."
User avatar
jackhackett
Posts: 1496
Joined: Tue Jun 10, 2003 8:52 am

Re: CP200d and fuse

Post by jackhackett »

Things most likely to blow the fuse when the radio is off... protection diode, capacitor, RF final.
Do you have the detailed service manual?
User avatar
arlojanis
Posts: 1009
Joined: Mon Jan 28, 2002 4:00 pm

Re: CP200d and fuse

Post by arlojanis »

I do not have a manual. Do you know a source? I know that the off-on switch switches to ground, so battery positive is applied constant to some things.
"The world runs on radio."
User avatar
jackhackett
Posts: 1496
Joined: Tue Jun 10, 2003 8:52 am

Re: CP200d and fuse

Post by jackhackett »

I have one for the CP200, but not the CP200D. I'm normally get them from MOL but can't check it at the moment.

The way the power works in most of the portables is the switched voltage goes through a MOSFET that is controlled by the power switch and microprocessor, and only things that draw a lot of current are connected directly to B+, such as the RF final and some voltage regulators. The regulators have an enable pin that's connected to switched B+ so when power is off they are disabled.
I've seen RF finals get leaky and draw current when the radio is off, so that's a possibility.

There should also be some reverse polarity and over voltage protection diodes across B+. Was the radio in the charger when the fuse blew? If it was you might want to check the charger's output voltage.

There are also filter capacitors across B+, if one of those is going bad that could blow the fuse.
Post Reply

Return to “MotoTRBO Portables and Mobiles (4xxx/6xxx) 1.0 Series Subscribers”