Thursday, March 31, 2011

Timewave DSP-9

Took the old Timewave DSP-9 out to look at again.
DSP-9 Top


The Audio output on this is a 'chipamp'  TDA2003 and when it went bad I ordered a TDA2006 because it is a pin equivalent but it did not work so I put it aside.  I looked at the data sheets for the two chip amps and it although they are 'pin' equivalent there are major differences in the circuit that the chips want to see according to the sample circuits provided by the mfg.  By changing some of the values I could tell the chip would come to life but sometimes it was oscillating and it would only run for a few seconds before overheating and shutting down.  Now I notice that DigiKey does have some of the older TDA2003 in stock and I think I will try to get the original replacement before attempting to change the circuit to get the newer TDA2006 to work.

2 comments:

w5kcm said...

I picked up a DSP-9 a while back at a local hamfest. The seller told me that the audio amplifier was bad. When I checked it the TDA2003 was completly gone. I installed a new one and it is working great now. 73, Randy, w5kcm

Paul Gerhardt said...

Glad you got it working. It is an 'easy fix'