Servicing a 1970s JVC JR-s301mk2 stereo receiver.

bad caps, resoldering, lamps, and more!

[@shango066]

Those capacitors are so evil in automotive modules with the heat and humidity they are exposed to.

[@shyguy2189]

Hi shango066 just like to say I love your video 👋👋✌️

[@Synthematix]

Yup thats why they coat the pcb's with epoxy

[@mdzacharias]

Wow! That bias thing woulda had me! And I'm pretty good with this stuff. Good work!

[@peyiots]

I commend you on your diagnostic and surgery skills! I admire you.

[@knifeswitch5973]

Fun tour inside a different JRs than mine. I nabbed a 201 a year ago on the sort of cheap. Quite a bit of difference cosmetically. Haven’t gotten around to it yet but did DB, output dc check and hooked it to the shop speakers. Older low and mid level JVCs never quit surprising me as to how good they sound. Always interesting to watch your troubleshooting methods. Nice job

[@SIXSTRING63]

Great videos JP! Big thanks to Shango066 for sending me to your channel a few years ago. You two guys keep me going on this solid state stuff. I’ve been repairing tube gear for the past 15 years and recently got into trying my hand at this stuff. Just repaired 2 out of 3 old receivers, an old Luxman and a Yamaha. The 3rd is a Pioneer quadraphonic that Shango066 did quite a few years ago and said he’d never do another. I can see why after getting into that. Still sitting on my basement floor after giving up 6 months ago. Just a nightmare getting boards out with the post and wrap connection setup. Too bad because it is in pristine cosmetic condition. Get some radio signal using my signal tracer but output is dead. One of these days I will get back to it when my bench clears from guitars amps and guitars to repair.

[@markrhine5809]

Dear Mr. Pier, Just an excellent video..

[@aarongunter5582]

You’re awesome man you and shango066 are good people

[@cjay2]

Good call there, finding that those were two-junction diodes instead of three. With no evident crossover distortion, I would probably have just sent it on its way.

[@zulumax1]

Me too, that one went right by me. I thought they usually showed the three diode symbol on the schematic, like the auto bias thermal compensation ones.

[@TheCondoInRedondo]

I had one of these in college. It also had a matching cassette player/recorder. When the next model came out, JVC made a big deal that the audio chain was 100% DC coupled. Bass was much better. Used this to drive a pair of AR-90s.

[@FrankenShop]

Wow, good diag, well done!

[@tinman4919]

MAN i loved this.!!

[@MedusalObligation]

I am currently elbows deep in my personal JR-S300 MKII. Many leaked and dead caps. Including the 10000micros on the PS board. When it died, I replaced it with a modern Sony rcvr. I just don't like the sound of it. It forced me to delve into the repair of the old JVC. It just drives my old Design Acoustics D2 and D6's perfectly. The matching tape deck is probably beyond repair due to plastic degradation, but it was a good competitor to Nakamichi when new. And the JLA-40 turn table still plays fine but again, due to plastic degradation, is a fully manual table now. I love that these are off the radar, makes donor units inexpensive.

[@phillanassa759]

Edit: They make a semi flexible point file that's gentler on contacts than paper, leaves no residue to speak of other than what is being removed, and allows you to clean the non movable contacts with the reeds removed. I add a little flux to make them easier to come out when they pee. You are right, the discrete 301 sounds better than the 500 series. I just did one of each with matching JVC Turntables, which are direct drive a-la' Technics, with a better tonearm than the 1200 series, thus a better sound IMO. I replace most of the protect relays when I can or when I can get by with a simple rewire to make something available today, unless it's mission critical. +1 on the Faderlube, good for the device while maintaining the 'feel' of the sliders. +1 on the plastic switches. Cromolyn was the best for pots and switches, but Mr. EPA made it go away. I had some up to a few years ago, might have some around here somewhere! All the Matsushita caps pee, like a drunk on a bender.. I just LOVE recapping the Technics RS series open reels, with upwards to 200 of them to replace. Followed by new cork brake pads, and typically heads or a head alignment. People love to tweak on those mini-cap screws, thinking it'll sound better, never mind cleaning the heads and tape path, just adjust the heads every 5 hours..... .lol. AS I said, I like to add some flux when DE soldering these caps, even if the wick has it already.. but seeing so many at one point I decided to "move it on up to " Hakko DE-soldering station for just such an emergency, it's nice when stuck doing the aforementioned Technics open reels or anything with the Mightyshitty caps aboard. I am basically sourcing the same caps for the same reasons. I will go the extra step and use something like Fine Gold or a tad better when replacing any of the Low Leakage Low ESR caps in audio critical positions.. such as the phono stage and preamp, tone controls-EQ. Along with the more popular transistors I seem like the 2SC458's I'm starting to see more Tantalums failing as well. Just recently started going through my personal 'Sui 8080 non Dolby. I got it a while back from someone that decided not to fix it, which needed a lot of work.. all bulbs, meter velum, wafer switches for the lighting, controls, metal film resistors on the speaker board, alignment, speaker relay, deep clean, alignment,.., wihth all the typical 8080 and 9090 failures plus needed factory required updates. His loss was my gain. I actually like the 8080, especially with running a more efficient speaker something like the JBL's, Altec's, anything with good 8 ohm sensitivity approaching or exceeding 100db 1 watt/meter @ 8 Ohms. This is the first video of yours I've watched. Shango rates you highly along with Bob Anderson, and I heartily agree on both counts! Both Liked AND Subscribed , looking forward to your other stuff, maybe its time for a marathon viewing session... like I did with Shango after I discovered him some years ago !!

[@scrappy7571]

I recapped my JRS 401, that I bought new in '78. It had Elna caps and the leaky ones were on the equalizer board. They used an IC 1457 that was the source of a channel dropping. Replaced it with a modern IC using and adapter, and the sound improved dramatically. JVC definitely fly under the radar compared to other receivers of the era.

[@JordanPier]

What did you use in place of the ha1457?

[@scrappy7571]

@@JordanPier Brown Dog makes an adapter, I had them install OPA604. They now sell this as an option. From what I could find, 604 is a good replacement, and works with the ps voltage on the equalizer board. Sound was noticeably improved. There are guys that rebuild mixer boards and they replace all the 1457's with 604. Also, from poking around on the net, the eq board is a common source of problems, due to caps leaking. I had recapped the board but still had a channel drop until the IC's were replaced. I enjoy your channel, thanks for the good content!

[@Texan1048]

Wonder if that's what's wring with mine, have cleaned and replsced the 15k slider... increasing it past 0 derps the meters out, 1 tick down and the relay protection engages. I've recapped and reflowed the EQ board, wondering if its those 1557s. I hsve 604 on hand

[@douglasallen9428]

Excellent! Many years ago, I actually came across one of these receivers at a thrift store called Cause for Paws, but they wanted $225 for it as-is….

[@mdzacharias]

Good old Chemtronics 10-50L solder wick. Best I've ever found!

[@JordanPier]

Yes. B&d sells it the cheapest. by far the best and I use it alot. Prefer it over a desolder station

[@mdzacharias]

@@JordanPier Yeah, Bud at B&D is my guy - has been for 20+ years. I'm retired now, wish I had more business to give them.

[@jdmccorful]

Interesting. Thanks for the look.

[@vfdffdd2675]

Great amp. Best for me is JVC AX1100

[@kingcrunch85]

These are nice rigs. I just got me a JR-S300 MK I for a bargain.

[@willardhendrix9546]

Hey,Jordan do you have a video on replacing the lamps in a jvc Jr 600?

[@nathanzimmerman5846]

Thanks JP for another great video. Shango sent me your way and I have subscribed to your channel. I have a question, do you use a dummy load at the speaker terminals and connect your scope there to check the signal on a receiver/amplifier? I have been mentored by a friend who had a electronics repair shop but he did mostly TV’S. If you have time to offer any input I would appreciate it thanks.

[@JordanPier]

Yes, I always simulate a speaker load. Big 500w wire-wound resistors. It's not possible to conduct most amplifier testing without a dummy load.

[@zulumax1]

That sure had multiple issues, one after the other. How many hours did you spend on it total? I had an amp that had pins on the board I had to access like this one. I disassembled a scrap molex connector to rob the round hollow pins with wires attached to them to make some test leads. Makes you wish you could get the engineer who designed it to come down and work on it. I don't think I would have thought of someone changing that diode with the wrong one. Great job, I love seeing how other techs do things, like your recapping method. Glad you shared that. No right way, many paths up the mountain, works for you.

[@JordanPier]

I think with all the problems this was about a 2.5 hour time investment

[@andershammer9307]

I had a JVC JR_S201 and it was ok but it had a problem right out of the box. One channel was out. Turned out to be the protection relay contacts. I eventually got rid of it and went separate preamp and amp.

[@humoursque8447]

Need to change the dialling bulb for the JVC JRS100 tuner. Is it a straight forward procedure? Thanks in advance.

[@JordanPier]

Requires small tools, removal of the faceplate and a steady hand with good soldering skill.

[@624radicalham]

Can we actually hear the radio after it's been done?

[@dennis2494]

I had a receiver like that one and I loved it, but I am pretty sure mine had a round toroid power transformer

[@adaboy4z]

Excellent detective work. Now can I send my JVC S201 to you? 😅

[@JordanPier]

Sure. Inbox me : vintageavrepair at gmail dot com if you wanna talk about it

[@larsmichael3383]

Thanks very interesting, so a too big difference in hfe of the drivers caused the missing bias on the npn's.

[@Poppinwheeeeellllllieeeeez]

Noice! JVC had some nicer gear. Did you ever use a Hawko desoldering pump? I was going to grab one. Currenly using wick and a pump, but find pumps really not that effective.

[@JordanPier]

Always been a wick and bulb guy. Hard to find desoldering bulbs nowadays. Hope mine hold up for now.

[@georgeham3190]

Hi Jordan where can we contact you for audio repair.

[@JordanPier]

I work for classic audio repair. Look us up on Google and give us a ring.

[@markrhine5809]

Good evneing Mr.Pier, I heard you say in the video, your soldering temp is about 800 degrees, may I ask you a question, I am really just a beginner, I have built some projects and I am getting ready to built the Tecsun 2P3 kit. Would you recommed that my PCB be cleaned prier to building the kit? I hope you do not mined the question. Your channel is the best on the internet. Have a nice day.

[@JordanPier]

It's probably not necessary to clean the board prior to assembly. If it concerns you then use 99.9% isopropyl or denatured alcohol to clean the board.

[@bikdav]

I had the JR-S200mk2. You're right about the overall (not so great) integrity. But, it got me by until I upgraded later.

[@Nirky]

Automatic thumbs up.

[@peterjmcgee4680]

I just turned this video on did you get that on eBay I may been bidding against you that same one was on eBay

[@JordanPier]

Nope.customer machine

[@Synthematix]

I tell you what, JVC are not the company they were years ago, at the local CURRYS electronics store here in the UK JVC are now a "shop brand" they bought the rights to the name for hifi and slap it on any cheap junk, SANDSTROM is another brand using the JVC name, its all hideous quality stuff. as for tape decks of the era, the three best sounding decks ive ever heard are from JVC, TEAC and OPTONICA (Sharp professional) The Optonica RT3838 is the king to my ears, its only a dolbyB deck and 2 head but damn it sounds good, every single part in the tape path is 100% analog, no digital dsp rubbish here, if you can get hold of one keep it because im sure you will agree it was the best 2head deck ever made, beautiful machine, built like a tank and really high quality construction.

[@zx8401ztv]

So it was lack of bias that made it sound rough. Transistors stop conducting at the cross over point ? It's been years since i repaired an amplifier and i've forgotten bits :-( That's a very nice tuner, very appealing fasia.

[@1sostatic]

It's not just me then! ! ! !-- Open up equipment that is "NOT" designed to be easily serviced ...and oh yeah ...my favourite ..."someone's been in there before me and dicked about with component values"...I had a situation once that wasted 2 hours of my life chasing down a fault that didn't exist; because some prior invasion of the unit by persons unknown swapped standard NPN/PNP for Darlington output power Transistors ... I didn't think that the first step is to strip out the heatsink assembly and look for that. aaaAAARRRGGGHHH ! ! ! !

[@JordanPier]

Yep. Totally hate that crap.

[@shawnjenkins8707]

I have an amp just like this one!! But it died..

[@summerforever6736]

Time to invest in a solder sucker to speed up your work!no?