Neal and all, thanks for the replies. I was able to solve this one. FR4, a 6.8 ohm 1/4 W fusible resistor was open. This resistor is located on the collector of TR 10, 2SD794 in the power supply area. I didn't find it at first because I was measuring voltage drop across all the low value resistors and this one did have an approximate voltage drop that I would expect to see across it, so I didn't suspect it to be open. Only later when I had an ohm meter in the area did I notice it to be open. Whats worse and I don't know if I should even admit this to the list, is that the customer brought in the instruction book with the unit and I had shelved it with the top cover so I forgot about it. When I went to install the top cover, guess what I found inside the instruction manual? The schematic. Figures. So if anyone ever gets paperwork come in with a repair, look through it for a schematic. The collector of the TR-1's now measure 3.0V rather than the 1.6V when it wasn't working. Gary McCartney McCartney Electronics 7134 Fife Rd, RR 7 Guelph Ontario Canada N1H 6J4 Fax: (519)821-1530 email: number63@xxxxxxxxxxxxx Neal Hartley wrote: > > Hello I once had one with the same problem and it turned out to be the > actual play/rec head had moved back in it's plastic mounting bracket so not > in complete contact with the tape. > Regards Neal > ----- Original Message ----- > From: "Gary McCartney" <number63@xxxxxxxxxxxxx> > To: <techassist@xxxxxxxxxxxxx> > Sent: Monday, May 27, 2002 4:59 PM > Subject: [TechAssist] Akai cassette deck model CS-M4 no audio out, schematic > required > > > > > This Akai cassette deck model CS-M4 has no audio output. With a signal > > tracer, I only get audio into the emitter of the first transistor after > > the tape head, which is TR-1 (one TR-1 transistor for each channel). The > > B+ on the TR-1 transistors collectors is only 1.6V so I am suspecting my > > B+ is being pulled down somewhere. I've replaced the TR-1 transistors. > > I've cleaned the internal rec/ play switch and tested the continuity of > > it's contacts which all checks ok. The circuit is too hard to follow on > > the pcb so I need a schematic to fix this one. > > > > Thanks for any help. > > > > > > > > Gary McCartney > > > > McCartney Electronics > > 7134 Fife Rd, RR 7 > > Guelph Ontario Canada N1H 6J4 > > Fax: (519)821-1530 > > email: number63@xxxxxxxxxxxxx ------------------------------------------ To REMOVE your email address, click here: http://www.tech-assist.org/unsubb.html To CHANGE your email address, click here: http://www.tech-assist.org/change.html ------------------------------------------ ***NEW*** Tips Added Instantly!!!*** Submit Repair Tips here: http://www.tech-assist.org/secure/tip/