Hello From JiggerMan

[JiggaMan]

Hi I'm Aaron from pittsburgh.

I am senior to repairing cb radios but very new to repairing car audio. I have tools, soldering gear, power supplies and a scope and all that. I have a pile of broken car stereos and amps so I decided to dig them. This online community has been very helpful so far.

I got through my first project ok. I had a nice pioneer with bad output chip in the back. I had audio signal and power to the chip but no output. ONce I unbolted the chip amp I noticed the big hole blown in it. (that explained the blown fuse when I got it..) I got a pal007a chip for $8 on electronix.com and put it in. it works perfect now.

Thank you everyone for welcoming me here.

My question is, when I am working on audio output with no speakers connected to channels, do I need a dummy load like I do working on cb and rf radios? Could anyone elaborate on this for me?

Thanks,
Aaron Miller from Pittsburgh
Cb Handle is "JiggaMan" 32cbshop.com

 

[lndm]

Hi JiggaMan
Audio amplifiers are typically not mismatched to an open circuit load the way a transmitter can be. Broadly speaking they strive to be a voltage source, with a low Zo.

I would use a dummy load anyway. It will ensure you get the picture from a working point of view. Dummy loads are also essential when working on valve equipment. Without a dummy load, a high signal voltage could develop across the devices that might destroy them.

 

[JiggaMan]

ok thanks I understand. Thanks for the reply.

Aaron

 

[lndm]

Good luck with the forum. I hope it works out well for you.

 

[Cal Weldon]

Hi Aaron and welcome to the forums.