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Proton anyone?

I have a Proton 320 clock radio, think it was 5$ at SA. It's my favorite clock radio edging out my Boston Acoustics Solo. The Solo has better sound, but cumbersome controls.

I also have a Proton AL-205 speakers. They're good sounding with a 5 in woofer and 1 inch tweeter. I've used them as table top speakers, but aren't currently in use. I'll admit I'm lusting after the power amps mentioned in previously in the thread.
 
airframer85 said:
Proton used to make NAD equipment according to other threads here. I can't wait get this D940 up and running so I can play with the cartridge loading settings.
Click to expand...

Often Proton and NAD used the same components, although I have liked most of the Proton equipment I have owned and thought the majority of what NAD produced was unreliable garbage. Because NAD uses so much more plastic than Proton and designed in the UK, I jokingly refer to the company is Nearly Amstrad Dreck.
 
Proton in the Netherlands

I own a Proton 1100 pre amp and the 1200 amp and are very pleased with them.
Just had a relay replaced and the units cleaned.
Sound like new again.
I use them with the Translator Reference speakers (Dutch design from the 80's)
Maybe I will sell them in a couple of months and buy the van Medevoort MA260 amp with integrated DAC.
Does any one have this one already?
It was introduced october 2011.
Maybe people can let me know their opinion about this amp.

Thanks in advance for your replies.
 
I just discovered this forum as I was trying to resurrect my D940. I bought this back in 1984 I think and used it regularly but then retired it when I moved to multichannel sound. But the fact that it had pre-amp out and mains in connectors made it ideal for my DBX Soundfield 10 speakers which require active equalisation. As an aside I can't use my DBX speakers at the moment since no modern AVR has those connectors and you can't path the equaliser into the tape recording path with digital audio these days.

I recently unpacked it to see if it still works and alas it seems one channel has failed. Playing any content through it only gives me decent sound on one channel, the other is very faint and hardly audible at all. Occasionally when first powered up both channels will run but in a few seconds the bad channel drops out. Also the volume control appears to have gotten dirt in it and is crackly and based on other posts in this thread, it looks like a major job to clean it out.

I don't think it's the power amps since if I inject a signal into the mains in connectors, both channels sound fine.

I did find a circuit diagram on the net recently but my knowledge of electronics is minimal so I am hoping to find ask a coworker who is a power systems engineer but tinkers with CE stuff to see if he can see anything obviously wrong. I suspect it's probably a cap or something (I hope) and then I can bring the unit back to play some of my LP's!
 
more likely it is a dirty switch or pot. exercise all the switches and knobs and see if it changes. regardless a cleaning is called for with gear this old.
 
Agreed, I doubt the problem lay in the main amp- the input selectors on these receivers are notorious for becoming intermittent and within a year or so after every cleaning, I'd have fiddle with the selector in order to get both channels to play. The real forte of the D940 is its dynamite little main amp which has 7 dB of headroom and the ability to drive high loads. Audio magazine found it more powerful than a 90 watt integrated.
 
Thanks for the replies.

- on the cleaning front I did notice that as I twiddled the volume knob I could hear some static and also as I switched inputs I could hear similar static. So a faulty connection on the selector switch might well explain why one channel is not working. That's a repair I might be able to do myself so some pointers on the appropriate way to do it including recommended fluids or sprays would be very helpful

- DPD was one of the reasons I purchased the receiver plus a very good review from Julian Hirsch (RIP) in Stereo Review at the time. I have had it going quite loud driving my DBX speakers with their two woofers, two mid range and 4 tweeters and hardly ever saw the DPD light come on. So it would be good to get this back to working condition again.
 
Caig Deoxit is a good choice for switch/pot cleaning.

*Julian Hirsch tested the AA-1200 amp for S/R; Ken Feldman tested the D940 for Audio. They both got rave reviews. Bridgeable- very unusal in a rec'r. I recently retired my D940 I bought new. Still works & is super mint but the FM tuner display won't reflect station changes now.
 
I know I bought the unit based on a review from somebody at SR but given how long ago it was, it's easy to recall incorrectly. As yourself I love the unit and would be dead keen to get it going.

Lots of products on the Caig site. Which one do you recommend?

Thanks
 
Well no luck. The pots and switches are sealed and the only access appears to be from the front when I removed the plastic knobs. I can't get at the backs unless I work out how to remove all PCB on the too. I can't imagine squirting deoxit in from the front is going to do any good since it won't penetrate into the inside of the switches and pots.

Any other suggestions?

Thanks
 
Yea, it's all coming back to me now. A friend that did servicing on mine had encountered the same problem. Lost contact with him so I'm at a loss as to how he addressed the issue. :dunno:
 
A month or so ago, I was looking for a cheap cassette deck to listen to while I work on the cars. Answered a Craigslist ad and bought home a Proton 740 with Dolby C, DBX, and the guy threw in 300 top quality pre-recorded tapes. Instant library. All for 20 bucks. Since it was easier, I tested it in my main system, and, Holy Cow, this deck easily trumps my maintained marantz and Akai decks! Very musical. Very Nad. Zero problems, auto repeat and track search too. Dark brown metal face and great styling. It is staying in my main system!:banana:
 
62caddy said:
Yea, it's all coming back to me now. A friend that did servicing on mine had encountered the same problem. Lost contact with him so I'm at a loss as to how he addressed the issue. :dunno:
Click to expand...

Rats! Short of paying money for a repairer to look at it, somebody at work suggested I try to drill small holes into the switch and pot and squirt the Deoxit into the hole! Might work so long as I don't drill into something important :no:

Anybody who has other ideas please feel free to contribute
 
DCinDC said:
read the DEOXIT sticky then. It should explain how to get the cleaner in there.
Click to expand...

Nope - nothing in there at all about what to do.

On their web site they say

4. Potentiometer Maintenance

The following guidelines have been established based on the experience and feedback of technical professionals, end users and our own years of testing and evaluation:

Sealed pots:
1. Found in newer equipment, may be difficult to restore, and should probably be replaced.
2. Occasionally if the pots are not totally sealed, you may be able to treat it in an ultrasonic cleaner
using a 10% solution of DeoxIT. Contact a CAIG representative for specific recommendations and
instructions. Call 858 / 486-8388.


That is not encouraging. If I could remove the pots I might try drilling but they appear to be buried in the front panel and major surgery to get them out.

I plan to spray like crazy down the shafts and twirl them around and see if any cleaner seeps inside and removes any gunk that might be causing the problem.
 
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