My First C-J Unit!

[Tzed250]

Hey y'all, long time admirer of Conrad - Johnson products, first time owner.

My uncle gave me his old stereo which included a PV-1 serial number 119!
I think that sometime in the late 1980s the fuse holder came unsoldered and touched something it shouldn't have, blowing one of the woofers in his Harbeth HL Monitor speakers (the woofer was replaced at that time with an updated Harbeth unit).
He replaced the PV-1 with an NAD pre-amp, which I also have.
Power is an early Bryston 2B, which makes the original system age-correct 1978 or so?
And quite high-end for its day I would think.

There is also a Thorens TD-165 which of course is missing the dust cover and the anti-skate weights...

I'm going to be putting an IEC jack with integrated On/Off switch on the back of the Bryston as it currently doesn't have an On/Off switch of any kind.
I'd also like to put an IEC jack on the PV-1 in the interest of grounding safety (is that sacrilegious?) and also power cord rolling. I guess I could just change the current 2-wire power cord out for a 3-wire cord and ground the unit that way, with no or little alteration required.
In any event I'd like to download the wiring schematic to double check my repair ideas and test functionality before I power it up fully.

Thanks!

[admin]

Welcome to CJO, great to have you with us.

The PV-1 is truly a classic. I would do a thorough check over the unit as we are talking about a 4 decade old piece of electronics. I would actually be a little surprised if all the caps are still at spec after all this time. Obviously, you have to make sure there are no further loose components or short circuits.

As for adding an IEC plug, that sounds like a fun project. I'm really not sure what you are going to be adding by putting a ground wire on it? Are you just planning to ground the case? In all honesty, I would probably leave it with a two pronged design, or float the ground if you want to use 3 pronged cords.

All our available schematics can be downloaded in our troubleshooting section sticky post.

Again, welcome to CJO and let us know how things go!

[Tzed250]

Thanks for the reply, and the welcome.
Yes, that's a good idea to check the capacitors, and tubes, etc.
I guess I was thinking of safety in terms of grounding the unit. I know modern hi-fi sometimes comes with only a 2-wire power cord but those chassis must be double-insulated and so don't need the separate ground?
Some people think that adding a ground can cause a ground loop or hum/other noise but I figure I can remove the ground if it causes problems, and still have a polarized plug and the option to try different cords.
I am a little worried about having chassis ground and turntable ground on the same 'circuit', so that's something to look at.

I can't seem to find the PV-1 schematic in that google drive, is there more than one?

[Tzed250]

Never mind, PV-1 isn't listed in the Google drive files but the schematic is present in the download, thanks so much what a great resource!

[Big Dog RJ]

G'day mate, greetings from down unda.

What a classic set-up that is! A real true classic in every sense of the word- classic! PV1 is rarer than the Tasmanian Tiger... I guess there are more PV1's around and zero Tazzy tigers.

IEC outlets would definitely make more sense, if you're thinking of using higher grade power cords. As Admin stated, just make sure all the caps and other parts are upto spec on the PV1. I'm sure once these are checked and properly assessed, should be sounding mighty fine!

The PV1 is what started it all for CJ. The rest is history!
Cheers, and enjoy those fine tunes.
Woof! RJ

[Tzed250]

Thanks!

Now I'm struggling a little bit with wether to cut holes in it or no...

I have seen people put an IEC male on the end of a short new power cord, that way no big hole in the chassis and you can still try different power cords from there to the outlet. Pretty smart.Only requires enlarging the existing power cord hole a little bit maybe.

But the cheap RCA input jacks are bumming me out too, so maybe I'll change everything on the back, including removing the 6 auxiliary power outlets...

I mean I guess it's a pretty early unit but it's still a triple-digit serial number, not like it's #3 or anything.

Part of the fun of owning stuff is deciding on whether and how to mod it I guess!

[admin]

Never mind, PV-1 isn't listed in the Google drive files but the schematic is present in the download, thanks so much what a great resource!

Yes, we do have the PV-1 schematic. It's in the downloadable file, but also clearly listed as one we do have (so I'm not going to do any editing):

https://www.conradjohnsonowners.com/viewtopic.php?t=128

Available Schematics:

Conrad Johnson PV1 SCHEMATICS
Conrad Johnson PV2 SCHEMATICS
Conrad Johnson PV3 SCHEMATICS
Conrad Johnson PV5 SCHEMATICS 1
Conrad Johnson PV5 SCHEMATICS 2...

[Tzed250]

Sorry, it is clearly listed on your post here, but not in the list of files at the download site.
I didn't realize it was one big download, I assumed it would be one download per schematic so I panicked when I didn't see it, sorry.

But the file is indeed present in the download, so thank you!

[admin]

No problem.

I do make mistakes so just want to make sure it is listed in the post text and available in the download.

Hope it is of help.

[Tzed250]

Yes it should be invaluable as I check the circuit boards and make sure I don't have any bad parts. I can trace the 120v wiring as well to be sure it's safe.
My friend has a tube tester so it'll be fun to fire that up!