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jurb6006@gmail.com: Nov 05 05:48PM -0800 https://dl.dropboxusercontent.com/u/29948706/KR-4070%20Caps.jpg   In a Kenwood receiver. It is steel, not aluminum.   What is its purpose ?

M Philbrook <jamie_ka1lpa@charter.net>: Nov 05 09:15PM -0500 In article <4395ae50-6c53-4fa3-9f5c-7eb6264cfddc@googlegroups.com>, jurb6006@gmail.com says...   > https://dl.dropboxusercontent.com/u/29948706/KR-4070%20Caps.jpg   > In a Kenwood receiver. It is steel, not aluminum.   > What is its purpose ?   Not sure, I don't think it's being used a Mu metal, cause I don't see anything alarming there?   It could be there to enclose the rupthure if the caps explosed I guess ? Who knows. :)   Jamie

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Nov 05 08:23PM -0600 "M Philbrook" <jamie_ka1lpa@charter.net> wrote in message news:MPG.30a5d74ea1f4f217989d72@news.eternal-september.org...   > It could be there to enclose the rupthure if the caps > explosed I guess ? Who knows. :)   > Jamie   What was the original question?   Mark Z.

Michael Black <et472@ncf.ca>: Nov 05 10:01PM -0500

Jeff Layman <JMLayman@invalid.invalid>: Nov 06 07:47AM > https://dl.dropboxusercontent.com/u/29948706/KR-4070%20Caps.jpg   > In a Kenwood receiver. It is steel, not aluminum.   > What is its purpose ?   And, whatever it does, why is it asymmetric?   --   Jeff

N_Cook <diverse@tcp.co.uk>: Nov 06 08:40AM > https://dl.dropboxusercontent.com/u/29948706/KR-4070%20Caps.jpg   > In a Kenwood receiver. It is steel, not aluminum.   > What is its purpose ?   Is there any trace of someone having been in there before? On the extended part of the "U" , into the large heatsink, is there a purpose made anchor point there also ? A part left over, buggered if he could remember where it came from, but thought it best to leave it inside somewhere, JIC. Haven't we all been there at sometime , with odd bits of metal work? On that front I picked up one of those dash-board cam gizmos last week , with 1 second spaced stills setting, recording to SD, to suspend over the banch for when disassembling the next complicated mechanism, with no exploded views in a manual

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Nov 06 06:26AM -0600 "Michael Black" <et472@ncf.ca> wrote in message news:alpine.LNX.2.02.1511052201300.16969@darkstar.example.org...   > At least, that was in the subject header.   > Michael   Really tells me nothing. I work in audio, but Kenwood also is a major player in the amateur radio biz. SO, I would like to know more details. Type of equipment, model number, problems / issues, whatever.   Maybe I can be of help, maybe not. I cannot know until I have:   MORE DETAILS.   mz

ggherold@gmail.com: Nov 06 05:55AM -0800 > https://dl.dropboxusercontent.com/u/29948706/KR-4070%20Caps.jpg   > In a Kenwood receiver. It is steel, not aluminum.   > What is its purpose ?   Blast shield so when the caps let go they don't spread goo onto the nearby circuit. :^)   (Maybe electrostatic shielding it looks to be on the caps right after the rectifiers???)   George H.   George H.

Geo <nhhu-o3hu@dea.spamcon.org>: Nov 06 02:39PM >(Maybe electrostatic shielding it looks to be on the caps right >after the rectifiers???)   My guess too. Post-production development. They have used an existing board fixing hole. Possibly radiation into audio channel as one capacitor can will not be at ground potential - although if the cap was doing its job...   Remove and listen for difference.

"Tom Miller" <tmiller11147@verizon.net>: Nov 06 10:43AM -0500 <ggherold@gmail.com> wrote in message news:c145e6f7-4793-466c-b33f-ea16b063d042@googlegroups.com... > after the rectifiers???)   > George H.   > George H.   I there a fan for forced air cooling? If so, maybe it is for directing cooling air?   Just another guess.

jurb6006@gmail.com: Nov 06 08:22AM -0800 Pretty sure that is a Kenwood KR-4070. The question was originally posed on Audiokarma by a guy who services and restores vintage audio.   He also noted that he worked on one with a later serial number and it had no such shield.   That's pretty much all we got.

The Hammer <lhammer610@gmail.com>: Nov 05 01:25PM -0800 I am trying to fix a wine fridge. Avanti wine cooler EWC1201. "Thermoelectric Cooling System".   http://www.avantiproducts.com/products/id/424   Looks like a transistor is fried. Odd part number of   3DD13005MD   Apparently it is a part from China. I can buy in 10,000 quantity.   http://www.alldatasheet.com/datasheet-pdf/pdf/410811/JSMC/3DD13005MD-O-HF-N-B.html   Ic 4A Vceo 400V Pc(TO-220) 75W   NPN. It looks like it has a diode across it which I could always add externally.   I cannot find any cross reference for it. Does anyone have a generic substitution suggestion - even if I have to add that diode myself?   I came across:   http://www.digikey.com/product-detail/en/STL128D/497-12268-ND/2827113   This one is 65W. Has the diode. 10 Watts less concerns me.

Jon Elson <jmelson@wustl.edu>: Nov 05 03:40PM -0600 The Hammer wrote:     > http://www.avantiproducts.com/products/id/424   > Looks like a transistor is fried. Odd part number of   > 3DD13005MD   Just wondering, could it be a replacement for an MJE13005? I think that's a darlington.   Jon

"Ian Field" <gangprobing.alien@ntlworld.com>: Nov 05 09:40PM "The Hammer" <lhammer610@gmail.com> wrote in message news:21e3a8eb-8548-47d4-aa80-63bc329622cf@googlegroups.com...   > I came across:   > http://www.digikey.com/product-detail/en/STL128D/497-12268-ND/2827113   > This one is 65W. Has the diode. 10 Watts less concerns me.   You could probably liberate one from (at least) 20W CFL, but the Ic rating might not be quite there.   The MJE13007 is rated 8A - if its a half bridge circuit (2 transistors) you should replace them both anyway.

"Dave M" <dgminala@mediacombb.net>: Nov 05 04:42PM -0600 Looks like the BUL38D is a close match to your transistor. Mouser has plenty in stock http://www.mouser.com/ProductDetail/STMicroelectronics/BUL38D/?qs=sGAEpiMZZMshyDBzk1%2fWi8oN7VHZ91Ok%252bCtFEGR%2fnKk%3d   Cheers, Dave M     Jon Elson wrote:

The Hammer <lhammer610@gmail.com>: Nov 06 06:47AM -0800 On Thursday, November 5, 2015 at 5:43:01 PM UTC-5, Dave M wrote: > http://www.mouser.com/ProductDetail/STMicroelectronics/BUL38D/?qs=sGAEpiMZZMshyDBzk1%2fWi8oN7VHZ91Ok%252bCtFEGR%2fnKk%3d   > Cheers, > Dave M   Dave, that looks like a perfect replacement! Thanks.   Larry

John-Del <ohger1s@aol.com>: Nov 05 11:30AM -0800 I was just ready to pitch this beast into the sweet bye and bye when my younger brother stopped me. It belonged to my father and my brother wants to repair it and keep it for sentimental value. Personally, I never liked the sound of it, but that's another story.   This quit working some 20 years ago when the bridge rectifier shorted and took out the power transformer.   Is a transformer something that could be found? Any idea where to look or what forum to join? Did another Heathkit model share the transformer, perhaps earlier incarnations?   Absent that, is it worth parting out or trying to sell the carcass on ebay? My oldest brother built it for dad and I can guarantee the wiring and soldering are first class.

dansabrservices@yahoo.com: Nov 05 01:28PM -0800 If you have the manual, check for the output voltages for the transformer. It wasn't anything special. You may find a new one with the same output voltages. IRRC, the AR-1500 was able to work from either 120 or 240V. If you know that it will be connected to 120, the search for the transformer should be easier. I may have the manual for that model around. I will look and post any info I have.   Dan

"jfeng@my-deja.com" <jfeng@my-deja.com>: Nov 05 02:50PM -0800 I think the AR-1500 was the same as the AR-15 with updated cosmetics. And the AA-15 was just the amplifier part of the AR-15.   There is a listing on eBay for a power transformer for the AA-15. If you are lucky it could be a direct replacement. Otherwise, it is probably pretty close, and you might only need to add another small transformer to power the tuner section.

Reinhard Zwirner <reinhard.zwirner@t-online.de>: Nov 06 12:20AM +0100 John-Del schrieb:   > This quit working some 20 years ago when the bridge rectifier shorted and took out the power transformer.   > Is a transformer something that could be found? Any idea where to look or what forum to join? Did another Heathkit model share the transformer, perhaps earlier incarnations?   > Absent that, is it worth parting out or trying to sell the carcass on ebay? My oldest brother built it for dad and I can guarantee the wiring and soldering are first class.   Maybe someone here   <https://groups.yahoo.com/neo/groups/heathkit/conversations/topics>   is able to help you.   HTH   Reinhard

"Dave M" <dgminala@mediacombb.net>: Nov 05 08:35PM -0600 If the part number on the transformer is 54-181, then you might be in luck. There is one listed at Play Things of the Past web site (http://www.oldradioparts.com) for only $15.00. I've ordered from them before, but not recently. they're legitimate folks. Be sure to follow the HOW TO ORDER instructions... it's a one-man operation, so be patient. The transformer is listed in the Power Transformers list (item 1372-053 (http://www.oldradioparts.com/2a23efl.txt). The only drawback is that they have a $20 minimum order, so you might spend some time with your AR-1500 and see if there might be something else you need to get for it to help fill the minimum.   HTH, Dave M       Reinhard Zwirner wrote:

"Ian Field" <gangprobing.alien@ntlworld.com>: Nov 05 07:28PM "whit3rd" <whit3rd@gmail.com> wrote in message news:30e74932-cb49-4afe-9290-1b7ba438b249@googlegroups.com... > (the switches and diode have lower losses at lower current) and use > multiple LEDs > in series.   It'd look pretty funny with multiple reflectors to fit over the multiple LEDs - and I'd have to scrap a lot of bicycle lights to get them.   The modified buck I'm using puts the LED in series with charging the inductor - and the catch diode gives it another bite of the cherry.

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