PV1 input jacks loose

[reelybored]

Just acquired what appears to be a PV1 (could be wrong) from my dad and the audio seems to cut in and out at times. When I move the rca jacks in the rear (wiggle up and down) and position them in a particular way seems to do the trick temporarily but the trick does not seem to last long and I have to do it again. I opened up the panel and there seems to be some give when wiggling the inputs. Anyway I might be able to resolve this? I will try and take some pics, maybe even a video this weekend if what I'm saying makes no sense. Thank you.

[admin]

First, welcome to the site. Great to have you with us.

The PV1 is is now 4 decades old so not surprising that it is starting to show its age. Considering that "wiggling" the RCA connectors brings back the sound for awhile I would presume this is most likely a cold solder/broken connection. I would open up the unit and check the solder points for the common input connections of the RCA jack circuits (presuming that this happens regardless of the specific input selected). While open, I would also inspect the unit for any obvious damaged components,... ie burn marks, bulging caps, etc.

Make sure the unit is off and unplugged for safety. Let us know what you find.

[AnotherJohnson]

If the jacks are actually loose, it is a sign of over 40 years of plugging in and unplugging. Depending on the jacks, this could be a simple matter of tightening a small hex nut holding the jack to the chassis. Roberto will have had a PV1 apart at some point so he will know if this is how the jacks are secured.

Another low hanging miracle fruit is De-Oxit or other electric contact cleaner. It would be harmless to spray and clean the jacks. They will need it if this is a legacy unit.

And yet another cheap and safe path is to change the interconnect cables. Cables age out and fail too. Get some cheap shielded interconnects at Walmart or Best Buy. If they solve your problem, get some good ones.

As Admin points out, there could be worse Gremlins lurking inside. If you decide to look for them by digging in, be careful. There are lethal voltages present, and because capacitors store energy, they can be present even if the the unit is unplugged. If you simply must probe stuff, keep one hand in your pocket, stand on a rubber mat, and probe with a chop stick. FWIW, if the capacitors are original, or even if it was recapped in the early part of the present century, it NEEDS capacitors. Even if they’re not bubbled, leaking or bulging.

It will not sound its best if this is not done.

You’ve got a nice bit of Americana there and it will be fun to get it working. Enjoy!

[reelybored]

Thanks so much for the input. Here are some pics of what I am working with. Again, I'm assuming it's a PV1. Forgive me as this is new to me.

[admin]

Looks like a PV1 based on the knobs but it's funny because I don't remember the front plate being rack mountable. Maybe I'm wrong or perhaps there were different versions?

Those inputs look pretty janky! A good cleaning would be in order. I would also just confirm that the connection issue is not with those RCA cables as they look like the dollar store brand. If you have the phenomena of the sound going in and out out with jiggling, regardless of which input you are using, then it would be an issue with a common signal line connection. Do you have a multi-meter with a continuity checker? If so, you could quickly check the continuity on each input. Again, you have to be a little careful with the caps as they can hold a charge. You can manually discharge the larger ones to be safe. Everything should be unplugged when you work on this.

Cosmetically, that unit looks really good. I don't see any obvious damage, it's not full of dust and crud,... looks like it was well taken care of for 40+ years. Somebody loved this unit.

[reelybored]

Looks like a PV1 based on the knobs but it's funny because I don't remember the front plate being rack mountable. Maybe I'm wrong or perhaps there were different versions?

Those inputs look pretty janky! A good cleaning would be in order. I would also just confirm that the connection issue is not with those RCA cables as they look like the dollar store brand. If you have the phenomena of the sound going in and out out with jiggling, regardless of which input you are using, then it would be an issue with a common signal line connection. Do you have a multi-meter with a continuity checker? If so, you could quickly check the continuity on each input. Again, you have to be a little careful with the caps as they can hold a charge. You can manually discharge the larger ones to be safe. Everything should be unplugged when you work on this.

Cosmetically, that unit looks really good. I don't see any obvious damage, it's not full of dust and crud,... looks like it was well taken care of for 40+ years. Somebody loved this unit.

As far as different versions, u got me. That's one of the reasons I questioned the version of this CV, lol. Believe it or not but two pairs of those interconnects are attached to two turntables. I will replace the other 2 pairs (one from CD player source, the other from the Power Amp, a Dynaco ST416). Any recommendations on interconnects that won't break the bank preferably

Unfortunately, I don't have a multimeter but may have to invest in one. Silly question, how would I manually discharge the larger caps?

[admin]

If cost is a concern I can give two recommendations for good RCA interconnects:

1) Blue Jeans Cable - https://www.bluejeanscable.com/store/audio/index.htm

2) Signal Cable - http://www.signalcable.com/analog_interconnects.html

I would recommend getting a multimeter. Not just for this project but it's good to have at home for diagnosing any kind of electrical issues. You can get a basic one for $30-50. Harbor Freight has some cheap ones which will get you 95% of what the ones pros use.

As for discharging caps: https://www.wikihow.com/Discharge-a-Capacitor

[AnotherJohnson]

Silly question, how would I manually discharge the larger caps?

It’s not a silly question.

People have died for not asking it.

My opinion is that you have to ask it, it would serve you well to find a good local technician.

FWIW, I use one of these.

https://www.stewmac.com/luthier-tools-a ... gITm_D_BwE

[reelybored]

Thanks for all the help, will leave another post when there are any updates to report

[Big Dog RJ]

Yes, that PV1 was one of those rare versions we sold only one unit of. If memory serves correctly, it was transferred over several owners between KL, Spore and ended up in Thailand with the Magnepan representative used in his personal ref system. It was termed the studio version or something like that. A real CJ classic!

It's pretty special to see one of these classics in fairly good nick. Looks really good. I'm sure with a little care and bit of service as advised, this unit will be singing some fine tunes.

Have a good one now,
RJ