Відео

Great Work 👍

Wow ! I have the exact same preamp that I bought back in the early to mid 80's.... Took it out of storage and now it is flashing RED.... I wonder what I should do and if it is worth salvaging...

We used the R-390 and R-1051 a lot in the Navy.

The phono stage on my HK 825 works but not all the time. I do hear the relay click and i can listen to a record. Also when i have my record player into phono input 1, if i switch to phono input 2 i can still hear the record even though it's not connected to input 2! Something has to be shorted across both relays for that?

BRAVO!

did you have to discharge any power from the monitor? i thought these old things stored a lot of power!

I’ve seen ceramic fuses that color before and also white. They’re generally higher amperage than the clear glass fuses. I’ve bought them in the store before labeled as microwave oven fuses.

Great to see this working. I have one I must repair, too.

Nice i had this one as a child

Excellent cleanup and diagnostics. I’ll have to look for the next part. 👍🏼

I just restored an sc504 and about 20% of the tantalum caps were leaky. I am now restoring another one and almost all the orange 22uf tantalum caps are bad. Nice video!

I bought myself an HP 1651B logic analyzer. Waiting for it to be shipped 😅

I laughed when you opened it up and said, "Oh my goodness" 😄. I have the XL24 and this video has been very helpful indeed. I found it all very stressful though, always thinking that I'm going to snap a piece of irreplaceable vintage plastic. Having to push a screwdriver in and apply pressure to remove pieces seems to be a recipe for disaster. I guess that's the trade-off for not using screws. Luckily, I got away with it this time... nothing broken. With luck, I won't ever have to do it again. Also, I ordered some fireproof sticky-backed foam to replace the slimy goo inside. Anyone acquiring one of these really should remove the foam. It turns into a nasty sticky mess. Mine was so bad it ended up all over the place. Edit: yes, I have ordered new foam, but turns out that the slimy mess was caused by the complete melting of the 'feed roll assembly' rubber rollers. So bad that I could wipe the black goo away (consistency of peanut butter) until I hit the smaller diametre hard plastic core. As there is no such part available on the Internet, this could mean forgetting about this project altogether. It's the single sheet feed ability I needed😥

Thank you for another interesting video. The culprit looks like it might be from steel wool and dropped in through the turntable cutout. As @rlgrlg-oh6cc suggested, it appears that someone atempted to "repair" it by twiddling all the knobs. Regards, David

I guess someone was adjusting all of the if cans, etc, trying to solve the problem with the short. Glad you figured it out.

I bought 530 for less than 100 working good

👍

Master Level diagnostic! That self test pass was a relief.

👍

Wow! Awesome work 👍. Just subscribed

Nice repair :)

Very nice work finding an unusual failure. I noticed the missing fuse cover early on and when you powered it up assumed you had spotted it too. Hard to imagine that anyone with knowledge of electronics and who would own an instrument such as this would be stupid enough to bypass the mains fuse. Thank you for another interesting repair. Regards, David

Great job on showing that power switch who's the boss!

👍👍👍

That is the first time I have seen a wet Tantalum fail short, I normally ignore them for shorts because I have never seen one go bad (apart from leaking).

LOL I was looking at that unit too I think, decided that I didn't NEED another counter.

Nice find and fix...

Beautiful restoration. Enjoyed watching the whole video. Congrats for your skills! Keep it up

That was really cool, I love he 330c. Please note that this is called a "board" and not a "bird". 🦤

Nice work!

The CRT for this model was provided by Sony (not built by Tektronix) The default type is 154-0667-00 with P31 phosphor (green florescence and green phosphorescence), medium short persistence. There was a special order version (154-0667-03) with P7 Phosphor. blue-white florescence and green=yellow phosphorescence), very longt persistence. You may have already noticed this during your testing. The CRT gun and electrical specs are identical.

Meticulous trouble shooting with interesting use of equipment... Very nice!

Very nice repair; well thought out logical approached, BROVO!

Another great repair at the Messy Lab! Your methodical process is fun to follow and the gear is always interesting. Thanks! - jrh

Hi! Nice project. Quick question. Do you know wich model is the PRE amp that goes with the SA series?

I had a great encounter with my 8350B and later on, with a 83592A 20 gig plugin. I'll listen to your video carefully and then I'll coment more. It is a nice instrument by the way, I love it. :)

Really good job to get the instrument working!

Thank you for another very interesting repair video. I hope you are able to find a reasonably priced plug-in for this fine instrument. Regards, David

Great✌

how do you think this compares to the sansui 221 receiver?

Didn't get a chance to watch the full video yet but do plan to when time permits. So in case you didn't point this out, that gunk is glue and not the capacitors leaking. Over time the glue becomes corrosive, so it all needs to go. My unit had that stuff on all the black wire cables inside too right at where they solder into PCB. Those connections were also corroding so I had to cut them off, re-strip the ends and solder back in. I recapped the whole preamp using mostly Elac audio caps which is what was originally in the unit. This preamp is well worth the effort! It sounds fantastic! As far as the relays, see my post to DS-bi3fz where I explain what causes the relays to burn up due to leaky 2SC2603 transistors. I was able to rewind my relays. If you decide to go that route, be very careful removing the relays. The pins break very easilly.

Nice save! always enjoy following you in your process, thanks for the content.-jrh

great job on a fine preamp with full descret circuitry. I am thinking of getting one. Any advice?

Nice work 👍

Thanks again for your outstanding work! I love that you will go the 9th degree to restore your projects. It reveals a deep understanding of electronics in your work.

Very interesting. Thank you very much!

Thank you very much there! Beautiful country yours, which unfortunately I never been. Greeting from Italy.

Well done. You always go well beyond with your repairs and restoration. Cheers from Australia.

Very well done! It's always a pleasure to watch you work through problems and find solutions. I look forward to see it in operation on your upcoming projects. Regards, David

Excellent job! It looks incredible compared to the way you received it! Also, very good diagnostic on the electronic issues and the wrong pot. A resistor in parallel was the best choice seeing getting a replacement would be very difficult.