Search results

I wouldn’t get hung up on the power supply assembly part numbers. Those numbers change during the course of production and not all the changes would be reflected in manual versions floating around the internet…that could just be a late production assembly because the part number is almost...

Sure do. Which style? The low-profile yellow zinc plated, or the tall chrome early “K fader” style? I have both.

Can you verify your meter make and model is Tougs M103? I can’t find anything like that…was trying to find the manual or at least specifications. Thanks.

Yes they are all mounted to the Power Supply PCB. And it depends on the caps. There are computer grade screw-terminal caps in my Ampex MM-1000 from 1967 that are still in-spec. But most of the caps used in something like a Tascam 38 can typically benefit from replacing at this point. Teac used...

Okay. Yeah something is not right for sure if both sides are running around 6V. That’s with J171 unplugged from the motherboard? Yes the main filter caps are on the Power Supply PCB, C806 & C807, and C812 & C813…pairs of 470uF caps running in parallel. Honestly that seems undervalued to me. I’d...

“Yeah, 6V.” 6V where? I keep repeating the question…between pins 9&11 or 10&11 of J171? Or both? Caps and diodes don’t regulate the voltage here. The regulators regulate the voltage. But a failed bridge or main filter cap or regulator can cause faults like this. Also, thanks for sharing the...

6V where? Between pins 9&11 or pins 10&11, or both? Is it still 6V? The audio chain will function at 6V, but that doesn’t mean it’s functioning right. What kind of meter do you have? If it’s still 6V I would also measure for AC volts between pins 9&11 and 10&11. It should be 0. Also, I...

I read the manual. So the tip temp is fixed at about 900 degrees. That’s too hot IMO. So, again, if you’re going to continue using that iron, you’ll have to work quickly. Where do you set the power knob? That controls the wattage. If it was me I’d make sure I had a right-sized tip (like maybe...

Look at page 82 of the service manual linked above…that’s exploded view 4. Looks like the power supply PCB is horizontally mounted below the reel motors and above the motherboard. Looking further on page 105 we have the schematic that includes the power supply. We can see the power supply...

Um, no? 106 pages? Full service instructions, theory of operation, exploded views, PCB layouts, schematics…it’s the full operation and maintenance manual…all the info is there regarding where the power supply is located and the wiring diagram…take a look…If that’s what you have and it’s not...

Thanks. Not trying to be a downer. What model Weller station? I generally like using something that runs at about 700 degrees. It needs to be hot enough to melt the solder. The wattage is what sets how quickly the iron can keep up with heat discharge. So a higher wattage iron will be able to...

Those trimmers will out-last any other potentiometer on that machine. They are not the problem. I recommend you find some scrap PCBs to use for practice with your soldering. What type of iron do you have? What type of solder are you using, composition and diameter wire? What are the specs on...

Okay. I got confused because a couple posts ago you said “I especially liked the 1/4" 2trk B for live stereo. From memory I think the Ampex head gap was a bit larger on that format.”

The motherboard of the 30 series is known to have mechanical failures of the solder joints, and I understand it can be beneficial to reflow those solder joints.

You have a 34 or a 34B? The 34B service manual is available online for free in pdf format: https://elektrotanya.com/tascam_34b_4-track_recorder_106pages_sm.pdf/download.html I’m not familiar with what all is different between the 34 and 34B. I don’t think it’s worth your while to hunt for...

Track width or head gap? You’ve referenced both. What are we talking about? Ampex adhered to the NAB standards for track widths in each format and they are outlined in detailed drawings in each manual. Ampex, at least as far as the AG-440 and MM series machines, did not implement any custom...

Do you have the service manual? It has pictures that show you were the major assemblies are, and how to access them, and all the pinouts with what is what.

Yeah that’s normal and tells you the meter motors, the coils and amplifiers, are working. You just, as you know, have no audio signal.

Sounds like everything audio is out. IIRC the headphone amp has a separate power supply from the main +/-25V audio power rails. Step 1: check the audio power supply.

I do understand and appreciate the “completist” syndrome. Which gap are saying was larger on the B? Sync or reproduce head? And compared to what?