What’s on *YOUR* workbench?

This one only powers on after it's been plugged in for a while. And it gets tired and shuts off after loading a tape

Is that a Panasonic? I haven't worked on them in years but it looks familiar.

Yep, like @jwin615 said, I'd start by checking electrolytic caps in the power supply.

The power supply might be in a shielded box under the main PCB, just follow the AC cord and you'll find it. Just like a tube amp or any other AC powered electronics, the caps can hold a charge so measure/discharge/measure them.

Shutting down after loading the tape could be a few electromechanical issues, but it could also be related to the slow power-on problem so try to resolve that first.

There is an infrared LED in the center of the tape deck that beams over to photodiodes on opposite sides of the basket to detect the beginning/end of the tape and in some cases when the tape is pushed in. Those can go wonky and cause it to shut down.

Depending on the make/model there is usually a rotary encoder under the VCR deck that the microcontroller uses to keep track of the state of the entire mechanism. Those can get dirty, you can usually pop the top off of them and clean with contact cleaner. It has thin metal fingers that ride along grooves that can bend easily so be careful with that.
9ux-osbfJ9FGwdtpzPJku3udVuWDkGBwSmNlH9dihRc.jpg


One of the various gears could have skipped timing, etc etc.


I'd start with the power supply issue so you aren't troubleshooting a problem you may not have.
 
Is that a Panasonic? I haven't worked on them in years but it looks familiar.

Yep, like @jwin615 said, I'd start by checking electrolytic caps in the power supply.

The power supply might be in a shielded box under the main PCB, just follow the AC cord and you'll find it. Just like a tube amp or any other AC powered electronics, the caps can hold a charge so measure/discharge/measure them.

Shutting down after loading the tape could be a few electromechanical issues, but it could also be related to the slow power-on problem so try to resolve that first.

There is an infrared LED in the center of the tape deck that beams over to photodiodes on opposite sides of the basket to detect the beginning/end of the tape and in some cases when the tape is pushed in. Those can go wonky and cause it to shut down.

Depending on the make/model there is usually a rotary encoder under the VCR deck that the microcontroller uses to keep track of the state of the entire mechanism. Those can get dirty, you can usually pop the top off of them and clean with contact cleaner. It has thin metal fingers that ride along grooves that can bend easily so be careful with that.
9ux-osbfJ9FGwdtpzPJku3udVuWDkGBwSmNlH9dihRc.jpg


One of the various gears could have skipped timing, etc etc.


I'd start with the power supply issue so you aren't troubleshooting a problem you may not have.
Yes it's a Panasonic HiFi VCR. Yeah I pulled the board last night to check the PS box. Getting that free is going to be a challenge. The fuse is good and the caps aren't bulging or corroded but that doesn't mean they're in spec. There's just one big honking 220v cap and yes I know what to do to be safe. Belts and gears are all intact and not excessively worn. Thanks for the photo sensor and micro controller info. That's very helpful. I'm gonna start with rebuilding the power supply
 
The power module usually plugs into the board, there might be screws going up from the bottom of the VCR through (or behind) a metal shield. They'll usually pop right out once the screws are out, they were meant to be quickly field replaceable while under warranty.
 
This makes me want to hunt down a VCR... (and a console television while I'm at it)

There's just something about a big VHS collection....
When I was growing up my dad had two VCRs and we would copy all the good movies we rented. We had a Huge wall that was full top to bottom of hundreds VHS movies in our basement. All the kids at school were jealous of our massive VHS collection. it was like having a Blockbuster Video in our basement. Still have all the VHS tapes hahaha
 
Making an 8u rack for the table. My first attempt at using stain. It was SO old. Also had a 10 cent sticker from a yard sale on the can. Maybe next time I'll get a new can and try it in my HVLP gun. Same story with the varathane. Don't bump the sides or the crusty rust will fall in! Rails and compressor comes tomorrow so a good day or two of curing before I assemble with screws and glue like a caveman.
IMG_1611.jpeg
 
Cabintech CT3680 "digital BBD" prototype test board is up and running on my test bench as of today. So far it's been a very easy chip to work with, but the paint by numbers part is done and it's time to let it tell me where it wants to go. I have way too many ideas on where to take this, but as usual I have to remind myself that's it's only a first go and baby steps often work best. :ROFLMAO:
 
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