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August 19, 2009

Comments

chazix

This seems like a good forum to add a note about speaker replacement. What I was after was a drop-in, more or less equivalent replacement for one with a bad voice coil. Here's the one I ended up using:

http://www.mcmelectronics.com/product/55-4624

...and the comment I put there:

"I ordered this in the hope that it would work to replace a bad speaker in a Proton 320 clock radio. It did, with a little bit of fuss. The main thing is that the magnet structure has a larger diameter than the original. There was slight interference from an electrolytic capacitor (100uF/25V labelled C615 in my example), located near the audio amp heat sink and towards the outer edge of the PCB. A touch of the soldering pencil to slightly lift the innermost pin of the cap, tilting the body of the cap toward the heat sink, was enough to allow clearance. I also needed to adjust the dress of wiring so that it wasn't pinched between the speaker magnet and the daughter PCB that holds the switches. Mounting centers are perfect. The fiber gasket is slightly thinner than original, so I used on extra washer on each mounting screw."

Some more detail: The MCM part (actually a Eurotec) has a lower free-air resonance, if that matters - around 120Hz vs around 160Hz for the original. I think the voice coil may be larger diameter than original, but I really didn't check. A 4-ohm version is made by Eurotec, I believe, but not sure if MCM carries it.

Menahem Yachad

Having serviced these for many years, I routinely replaced the failed lamp with a 3V turquoise LED, coupled to a 470 ohm 1W dropping resistor. If you do not use the resistor you will destroy the LED in less than a second.

There also an easy conversion in the circuit to convert the clock function from 60Hz (US) to 50Hz (Euro) operation.

Joyce

I had a 320 w-a-y back when. It was the best back then and I haven't come across any since that compare. All else cheaply constructed.
I really miss it. Someone made off with mine, too.

Ed S

Joyce, if you still want one they come up frequently on eBay for 50-75 dollars.
The clock radios from C. Crane are OK, if expensive.

http://www.oracleofinvesting.com/

This site was... how do I say it? Relevant!! Finally I have found something that helped me. Thanks a lot!

Barbara

I have a white Proton 320 which has a broken turning dial. It will only turn a little way and is very difficult to make it turn at all. Also, it picks up a "hum" when it is on (FM). It is quite an annoyance . My arm makes a great antenna but I can't hold that position for long. Does anyone have any ideas as to what I should do or is it time to get a new Sangean? I am not a radio engineer. In fact, I have very little patience with fixing things. My husband has to empty the vacuum cleaner!

MB

Still waking up to a 320 purchased in 1983 (or '84). It seems that was a good time to buy home electronics. These days 3 or 4 years is as long as things last!

New radio here

How do you set the time clock on the Proton RS 420 ?

Jennifer

I got 2 Proton 320's as a wedding gift in the 1980's. One still works and is used daily...the other never really worked well. Proton tried to fix it about 6-7 times and then gave up.

I love the glow and the beauty of the one we use. It is a classic. Thanks for reminding me how old I am!

David

Still have & appreciate my black P320, the proper color for its terrific design look, from about 1984. It's used pleasantly in a guest bedroom.

No mention of the very fine Schotz tuner in the thread, that I saw. Only my Bose WaveRadio eclipses this unit (substantially) for a tabletop clock radio. Supposedly a Taipei genius came-up with this unit (and the Proton line). It's been a great one for me now for 30+ yrs.

The slide-rule dial bulb has been replaced twice, but not the yellow'ish LED station position dot. Fomerly dial bulbs could be obtained cheaply through Proton's US distrib, in Cali, as I recall. Now I get them from RadioShack.

The bulb is a grain-of-wheat bulb OEM spec'd at 14V & 60mA according to my notes from years ago. It is prone to burn-out because it is mounted (slides down) a tight but openable metal sleeve wearing a plastic green translucent condom. Heat gets it. The condom has deteriorated some and no longer is used.

Currently a RadioShack 12 volt/50mA bulb is used. It is slightly larger in diameter so the sleeve had to be opened (bent) just a bit. Some Red heat resistant plastic material is used along the slit aperture (into which the etched plastic slide-rule dial also fits) to filter (color) the light for the dial, & maybe looks better. It's easier to see without being bright. Blue or ultraviolet would look good, too, probably, and more modern than the green.

A 12V LED would be good but should emit its light to the side. Otherwise, the light will shine down the sleeve instead of out through the aperture & dial.

All of this is simpler than it sounds. As long as the UL approved radio plays & doesn't get too warm (or hot, as a fire hazard) the bulb(s) will continue to be replaced! If the LED dial dot goes, it likely is not replaceable. It is a unique application ahead of its time.

PS: Would like to find a good working rendition of my old SONY Digimatic clock radio from the late '60's. Some had real wood cabinets. It had a black light Clock that was really special - though its sound could only be called average, or less! But it, too, is a classic.

Dave G

Great article. I've had several of these and just picked up one that has a curious problem. The battery backup isn't working right. If I cut the power at 4:44 (for instance), when I plug back in (minutes later), it's flashing 4:44. Seems it can save the time but not keep time while in backup mode. W/O battery, it will flash 12:00 after power is restored. Any ideas? Thanks.

Liz Pittman

my Proton 320 turns on but i can't tune it. does that mean the tuning lamp needs to be replaced? if so, where can I have it done? thanks, Liz

stefani

the volume on my 320 just died....anyone want it for parts?

Elaine

I have a Proton 320 with an antenna wire attached to the back of the radio. I still love the design of this radio but reception is horrible. I live in an apt. building in NYC. What can I do?

Sal Accardo

Recently, my Proton 320 developed a problem that occurs when the off button is pressed and then there is a loud continuous buzz. It stops when the unit is unplugged. Otherwise, it works fine when playing. Any ideas why there is this loud buzz and how to fix it?
Thanks for any help.

917-885-7405

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