Hooking a 1978 JVC 3100R VIDEO-CAPSULE Clock radio/TV to a 1982 JVC HR-7100U VHS VCR and everything is working great!

Didn’t have to do much with the VCR, just replaced all belts and polished the tape path with isopropyl alcohol.

The JVC TV just worked with no restoration!

The JVC HR-7100U VCR was featured in The Goldberg’s TV show during the early’80’s. If you remember that.

I have some experience with these, the VCR and TV can have bad caps depending on which kind JVC used. If they used panasonic capacitors they leak slowly, look at the negative leads especially they turn green. Remember these are approaching 40 years old now, caps will be failing. I would have at least ESR the low voltage filters in the VCR, and near the linear regulators on the power supply. Sometimes a bad cap here can kill a regulator transistor that can be difficult to find today. Years ago working professionally on solid state equipment capacitors caused the most problems hands down, sometimes killing very expensive transistors or IC's. EG...The 25 cent electrolytic kills a 15.00 horizontal output transistor which was very common back in the day or the open capactior on the FG line in a VCR kills an impossible to find servo drive IC. Not saying you have to shotgun all of them right away, not every cap kills something when it dies but there are some common known trouble spots that they should be replaced because they are known to kill other parts.

Hi tvman39, I was thinking about replacing some electrolytic caps in the power supply, sounds like good advice to me!

I recently bought a copy of the JVC service manual for the HR-7100U VCR and for another VCR, a Victor HR-3300. This should help with re-capping.

The Victor HR-3300 VHS VCR looks to be an older model with a copyright of 1978 on the service manual! Probably should replace power supply electrolytic in it. I finished replacing the old belts in that VCR and also polishing the tape path with isopropyl alcohol too. This VCR (the Victor HR-3300) is a very, very mechanical VCR with no ICs that I have seen so far.

I’ll attach a recent picture of it. Looks to be a Japanese model, with Japanese and English writing on it.

Hi to all,
Hi Brianweber4,

If the JVC HR-3300 has Japanese markings, please check on the rear label the AC voltage rating.
Japanese domestic voltage is 100VAC, not 117/120 or more like in the US today.

Running a 100VAC appliance on US voltage is definitely not recommended.

On a trip to Japan, i purchased in Tokyo's Akihabara "Electric Town" an autotransformer which converted Euro 220VAC to Japanese 100VAC.

Just being cautious here...

Best Regards
jhalphen
Paris/France

Hi jhalphen,

Thank you for your suggestion. Yes it says 100VAC on the back. I’m using a variac transformer set at 100VAC to power it up. I think it probably could take USA 120VAC but I’m being careful about that.

I also use a variac transformer to power up my Atwater Kent model 84, set to 100VAC as that radio had a notoriously ‘delicate’ power transformer. So far so good!

Here they are all together!

Very nice, clean the mode switch for sure to avoid any trouble. Deoxit works good. Mode switch problems can cause problems loading the tape to the head and ff and rew modes. I loved working on these earlier models. I have multiple top loaders and generally appreciate earlier models compared to the 90s common black boxes.

Looks like a JVC 3100 to me, not a 3100R. No radio in it.

.

The power transformer is not the issue in those A.K model 84s (or similar vintage A.K sets), it's the rotting rubber/gutta percha insulation on the power transformer leads causing shorts to ground, that fries the transformers. Replace the transformer leads, or resleeve the orginals, and you won't have a problem.
Regards
Arran

I second that..... Its very common to have to replace or resleeve wiring on pre wwII sets. Some postwar sets too. Many sets in general now have hard transformer wiring, handle it carefully and only when you absolutely need to and if insulation breaks resleeve as close to the internal connecton as possible. You may need to remove the shell around the transformer to feed the sleeving in or replace the wiring if feasible.

Yes speaking about flaking, rubber wire insulation, I did use shrink tubing where I could use it and the black paint on insulation, awesome stuff. It’s all set as far as that goes. I have read about faulty power transformers in AK radio sets, but seeing as my AK Model 84 is about 91 years old, my transformer probably is ok.

It’s a very nice and relaxing hobby working on vintage TVs, VCRs and radios, but I have to be careful as my wife now gives me ‘input impedance’ with new ‘old stuff’, Sometimes late at night, especially when it’s the weekends, she comes down stairs wearing Lingerie and interrupts my midnight soldering! Makes me too sleepy to come back downstairs again.

That machine is "it". The first-ever VHS VCR available. Very cool!

No, you should not run it at 120VAC, that would boost every voltage in it by 20 percent likely. Amazon among others sells 100-to-120VAC transformers:

https://www.amazon.com/gp/product/B000PC4JL4/?th=1

It is worth it for that VCR.