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#1
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
Free for Shipping: Eico Signal Tracer. Untested, no probe (looks like
it may not need one), Not stored well, but not bad either. Free for Shipping: Tube Tester, needs a bit of help, but claims to be "Dynamic Conductance". Banged up a bit but not overly so. If anyone is interested, I will come up with the brand. It is not one of the top brands, but not NRI either. Now that is out of the way. The Kenwood Receiver that wandered onto the porch over the weekend turned out to be (once the lint was removed) a KW55a AM/FM Receiver, 17 or 18 tubes. Outputs are EL84/6BQ5 PP with 12AX7 drivers. It got through all the passive tests OK, so when fired up and the meter on the variac stayed steady, I ran it for a few moments. Quite a sensitive front-end, the FM goes from 80.0 (!!) to 108.0. LOTS of clicks and pops and wheezes that eventually steadied out... definite candidate for capacitor replacement. But decent sound for all that _when_ it steadied out. http://radioatticarchives.com/images...55A_Potter.jpg is a picture of the unit I found at Radio Attic, but mine is NO where near as nice as the one shown. Questions for the assembled multitude, does anyone know: a) The approximate year of this unit? It has dialable AFC, no mute function, tape-head, Tape, and Mag. Phono inputs. Codicil: was it top/middle/bottom of the line in its day? b) There is a mysterious two-position slider switch dead-center on the back of the unit, between the pairs of output tubes, unlabeled. Any idea as to its function? c) I am going to word this carefully. I will not flog this beast on eBay, so I am not asking what it is worth. But, is it desirable to someone who might want to trade for it for something that I am actually interested in having? For instance, I would like an VINTAGE US-made (solid-state) AR tuner. Or a similar Scott or Sherwood or Fisher receiver, or some such. Suggestions welcome. d) I am half-tempted to do the full monte on the thing, clean it up to semi-pristine condition just to have a piece of Japanese Iron in the inventory if only for comparative purposes. Is this a silly idea? Pictures are available, of course, to the interested-in-trading. Thanks in advance. Peter Wieck Wyncote, PA |
#2
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
"Peter Wieck" wrote in message
oups.com The Kenwood Receiver that wandered onto the porch over the weekend turned out to be (once the lint was removed) a KW55a AM/FM Receiver, 17 or 18 tubes. Outputs are EL84/6BQ5 PP with 12AX7 drivers. It got through all the passive tests OK, so when fired up and the meter on the variac stayed steady, I ran it for a few moments. Quite a sensitive front-end, the FM goes from 80.0 (!!) to 108.0. LOTS of clicks and pops and wheezes that eventually steadied out... definite candidate for capacitor replacement. But decent sound for all that _when_ it steadied out. Probably needs a visit from a vacuum cleaner. http://radioatticarchives.com/images...55A_Potter.jpg is a picture of the unit I found at Radio Attic, but mine is NO where near as nice as the one shown. Those aluminum front panels like to oxidize, right? Questions for the assembled multitude, does anyone know: a) The approximate year of this unit? I sold a jillion of these at that Lafayette Associate store I worked at as a kid. Those were Lafayette branded. I'm going to guess around 1965. It has dialable AFC, That would be diasableable. no mute function, tape-head, Tape, and Mag. Phono inputs. Is the FM section stereo? I seem to recall that it was. Codicil: was it top/middle/bottom of the line in its day? Near the bottom. The EL 84 output tubes are the tip-off. I don't know if this was one of the Kenwood receivers with the *magic* output transformers that generated a lot of nonlinear distortion around 7 KHz to "brighten up" the AM. Try listening to the FM with good (preferably SS) power amp attached to the tape outputs. If that cleans up the FM sound considerably, then you've won the booby prize. The FM section could sound good, but if you've got one of the ones with *special* output transformers, the amp side is pretty nasty. My recollection is that the FM section of this puppy is really pretty nice, with good tubes and alignment. Lots of IF stages, and a FM RF stage as well - Maybe 4 FM sections in the tuning capacitor? b) There is a mysterious two-position slider switch dead-center on the back of the unit, between the pairs of output tubes, unlabeled. Any idea as to its function? Speaker phase switch? |
#3
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
Arny Krueger wrote: Probably needs a visit from a vacuum cleaner. Got that above the chassis, and a wipe-down with a strong ammonia-based cleaner... much to do below yet. Those aluminum front panels like to oxidize, right? Actually, the front panel and straight-from-the-front cosmetics are excellent. It's the back-of-the-house that needs work. The end that got the moist air from the dryer, I guess. Lots of pitting, no serious rust. And a very fine coating of what might be oil-boiler soot... slightly oily coating, but responds well to ammonia-based cleaners. I sold a jillion of these at that Lafayette Associate store I worked at as a kid. Those were Lafayette branded. I'm going to guess around 1965. That makes sense. It has a 'betwixt & between" look to it. More modern than the Scott & Fisher contemporaries, but not up to the 70s major bells & whistles category. Any idea of the Lafayette part number? It has dialable AFC, That would be diasableable. On a "click" switch. Yep. no mute function, tape-head, Tape, and Mag. Phono inputs. Is the FM section stereo? I seem to recall that it was. Stereo, most certainly. Good separation, high sensitivity. Codicil: was it top/middle/bottom of the line in its day? Near the bottom. The EL 84 output tubes are the tip-off. I don't know if this was one of the Kenwood receivers with the *magic* output transformers that generated a lot of nonlinear distortion around 7 KHz to "brighten up" the AM. Figured as much. And when I found out that the cover was both 'weighted' and 'expanded' (added a full inch in width, and about 4 pounds in weight), I knew what I had. Try listening to the FM with good (preferably SS) power amp attached to the tape outputs. If that cleans up the FM sound considerably, then you've won the booby prize. The FM section could sound good, but if you've got one of the ones with *special* output transformers, the amp side is pretty nasty. Actually, I ran the tape-out directly to another system at first. No discernable change when directly to the speakers. So, maybe not as you suggest with this one. My recollection is that the FM section of this puppy is really pretty nice, with good tubes and alignment. Lots of IF stages, and a FM RF stage as well - Maybe 4 FM sections in the tuning capacitor? Yep. Four sections visible inside the front-end box. And a full 10 tubes dedicated to the tuner section (Both AM and FM). It all comes back to a 6AQ8, however. One of the quirkiest tubes out there. b) There is a mysterious two-position slider switch dead-center on the back of the unit, between the pairs of output tubes, unlabeled. Any idea as to its function? Speaker phase switch? Maybe, I will clean further this evening, under the chassis, and see what-where-how it goes and is wired. Maybe even target a few caps at strategic locations. Peter Wieck Wyncote, PA |
#4
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
"Peter Wieck" said:
Kenwood/Trio KW55 a) The approximate year of this unit? It has dialable AFC, no mute function, tape-head, Tape, and Mag. Phono inputs. Codicil: was it top/middle/bottom of the line in its day? Based on model number and tube complement, I'd date this one somewhere around 1963- 1965.. EL84-based units were middle-class AFAIK. There's a manual available at: http://www.radioera.com/k-manuals.htm Scroll down a lot. Google shows some results from Japanese websites, bud sadly, I don't read Japanese. b) There is a mysterious two-position slider switch dead-center on the back of the unit, between the pairs of output tubes, unlabeled. Any idea as to its function? Check the wiring to the output transformers, it might be an impedance swith, or a speaker phase switch. Most of these early stereo units were fitted with a phase switch, to easily facilitate speaker connections. It was common practice to use different speakers for each channel then, so it may be omitted or bypassed if you're planning on restoring and using it yourself. -- "Due knot trussed yore spell chequer two fined awl miss steaks." |
#5
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
"Peter Wieck" wrote in message
ups.com Arny Krueger wrote: I sold a jillion of these at that Lafayette Associate store I worked at as a kid. Those were Lafayette branded. I'm going to guess around 1965. http://radioatticarchives.com/images...55A_Potter.jpg That makes sense. It has a 'betwixt & between" look to it. More modern than the Scott & Fisher contemporaries, but not up to the 70s major bells & whistles category. Any idea of the Lafayette part number? LR 440 keeps popping into my head. It could be one of the later tubed models that avoided the strange output transformers. It was one of the nicer-looking ones. |
#6
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
Thank you all for your various answers. Here is the last I will bother
you with it... Final tube count: 22. Including a strange little metal tube at one end (6CW4). Near as I can figure from pulling tubes at strategic intervals, there are 11 for the FM section, 3 for the AM section, 2 for the mag & Tape-head pre-amp, and 6 for the amplifier section. AM Band goes from 55 to 1600 (printed numbers) with some play to either side. FM Band goes from 80 to 108 (printed numbers) as above. The little slider switch is a 110/220V switch. With the controls fully cleaned, each tube & socket individually cleaned, it runs quiet, cool, no hum, hiss or pops at any volume. Dead silence on Mag. input at 3/4 volume, some hiss at full volume. The Matsu****a-branded tubes all test well above minimum on the Hickok, but a Royal PITA to go through all of them (Yes, the Hickok does test the 6CW4). This clearly does not have the "funny" output transformers. FM is quite nice, no funny-business. But AM is good and clear as well. I need dial lamps, one indicator lamp and a couple of spares. The dial lamps are fuse-type, I am guessing 8V as that seems to be a favorite KW voltage, but I will measure what is on the pins. The indicatiors are colored 1/4" threaded-base lamps. I may look foolish purchasing nail polish in the correct colors, but a with a cool enough lamp, this should work OK. The fuse-type lamps I will have to find. I will also have to take off the faceplate to get to them. A small price to pay. Thanks again. Peter Wieck Wyncote, PA |
#8
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
Jon Yaeger wrote: Peter, Those are 8 volt bulbs which you can get pretty cheap from Atlanta Light Bulbs www.atlantalightbulbs.com/ I'll send the manual in Word format via e-mail. Not doubt a vet like you has already changed the output tube coupling caps. If you didn't know already, ALL of the gray coupling caps are bad (leaky). And test some of the Nippon tubes - a lot of the 9 pin ones are crappy too. Jon: Thanks for the link, the manual, and the advice. I have bulk-ordered 50 x 0.05uf@600V caps, there are a bunch of them in there. And I observed that most of the 1uF @ 50V (electrolytic) caps are all swollen, so before this beast is permitted out of quarantine, all such will be attended-to. The remainder should be in my stock. Thanks again, Peter Wieck Wyncote, PA |
#9
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
"Peter Wieck" said:
Final tube count: 22. Including a strange little metal tube at one end (6CW4). A Nuvistor. Hard to come by, they're also found in e.g. Fisher and McIntosh gear from that era. Since our little friend Michaelson decided to use them in his Musical Fidelity "NuVista" range, they've become very scarce. Maybe you van try a scope parts supplier , they were to be found in certain oscilloscopes as well. I need dial lamps, one indicator lamp and a couple of spares. The dial lamps are fuse-type, I am guessing 8V as that seems to be a favorite KW voltage, but I will measure what is on the pins. Indeed 8V, a voltage and shape the Japanese manufacturers used up until well in the '80s. -- "Due knot trussed yore spell chequer two fined awl miss steaks." |
#10
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
François Yves Le Gal wrote: NOS 6CW4's can still be found for around USD 15.00 ea. Just snagged two at US$3.00 each from my local supplier. He has a few tubes in the back room, mostly TV types. Both are RCA, both NIB. As to their actual performance, that remains to be seen, but I do not have the need for now. He is more-or-less on my travel path. When I asked, he gave me a cross-eyed look, raised his hand in the air and went in back. Came back with them in his hand, said "three bucks each, want 'em?". Peter Wieck Wyncote, PA |
#11
Posted to rec.audio.tubes
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Note on Porch Find & Free Monday-on-Tuesday
"Peter Wieck" said:
NOS 6CW4's can still be found for around USD 15.00 ea. Just snagged two at US$3.00 each from my local supplier. He has a few tubes in the back room, mostly TV types. Both are RCA, both NIB. As to their actual performance, that remains to be seen, but I do not have the need for now. He is more-or-less on my travel path. When I asked, he gave me a cross-eyed look, raised his hand in the air and went in back. Came back with them in his hand, said "three bucks each, want 'em?". Seems like I live in the wrong part of the world. Any nice houses vacant there in PA, Peter? ;-) -- "Due knot trussed yore spell chequer two fined awl miss steaks." |
#12
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Note on Porch Find & Free Monday-on-Tuesday
Sander deWaal wrote: Seems like I live in the wrong part of the world. Any nice houses vacant there in PA, Peter? ;-) A few.... http://livingchoices.com/home/homede...767&mid=6 160 http://livingchoices.com/home/homede...517&mid=6 160 http://livingchoices.com/home/homede...939&mid=6 160 http://livingchoices.com/home/homede...966&mid=6 160 http://www.weichert.com/search/reale...pr=&x =25&y=8 And so forth. Keep in mind that the Philadelphia region was the home of Philco, RCA, Sylvania, A****er-Kent, Cunningham and more than a few other suppliers and supporters of the industry, and Westinghouse & GE had plants in the five-county area. So, stuff is thick on the ground. Peter Wieck From the Tobacco Road of Wyncote, PA |
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