20100317.ba v04_n324.bam.20100317 >From ???@??? Wed Mar 17 18:12:32 2010 -0500 Date: Wed, 17 Mar 2010 18:12:28 CST From: Old Tube Radios To: Old Tube Radios Subject: BOATANCHORS digest 4324 Message-Id: <20100318001228.EE992583AAC@minime.theporch.com> BOATANCHORS Digest 4324 Topics covered in this issue include: 1) FW: boatanchor @the porch. by "Brian Goldsmith" 2) Hammarlund LXR(?) available by Scott Robinson 3) Kansa City Boatanchorites by "Jack" 4) Johnson Ranger parts needed by "RICHARD GEORGE" 5) See Denice in QST by Richard Dillman 6) Halli SX-62A Last for now by "Allan Fritsche" 7) Re: Halli SX-62A Last for now by "Arden Allen" 8) Re: Halli SX-62A Last for now by spr@earthlink.net 9) Re: Halli SX-62A Last for now by Al Klase 10) Re: Halli SX-62A Last for now by Al Klase 11) Re: Halli SX-62A Last for now by "Arden Allen" 12) Recovering "Bumble Bee" Capacitors by "David Stinson" 13) Re: Recovering "Bumble Bee" Capacitors by spr@earthlink.net 14) Re: Recovering "Bumble Bee" Capacitors by "David Stinson" 15) Silly Signal Shifter Saga by "Wilson Lamb" 16) Re: Recovering "Bumble Bee" Capacitors by "David Stinson" ---------------------------------------------------------------------- From: "Brian Goldsmith" To: Old Tube Radios Subject: FW: boatanchor @the porch. Date: Mon, 15 Mar 2010 09:38:28 +1100 Message-ID: <5122A0D3A44E45429099DEE6DC2761AD@pcbriang> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit -----Original Message----- From: ray jefferson [mailto:ruetama7@gmail.com] Sent: Monday, 15 March 2010 9:11 AM To: brian.goldsmith@echo1.com.au Subject: boatanchor @the porch. DearOM Saw your boatanchor boasting and thought you might help mr. I was enrolled with Boaranchors @the porch.com for some time and let it drop. I want to re-enroll but need the proper e mail address to do it. Can you tell me the proper way to go about getting enrolled again. Thanks for your help. Ray Jefferson, w7fni.....since 1934 Date: Sun, 14 Mar 2010 16:34:59 -0700 To: Old Tube Radios From: Scott Robinson Subject: Hammarlund LXR(?) available Content-Type: text/plain; charset="us-ascii" ; format="flowed" Folks, Said receiver (designation from my leaky memory) was been stored in a damp garage for a while. The cover and bottom plate are in place, so the chassis is fine. The front panel is lightly rusted, and everything seems to be there. I can't cope with another 60 pound radio, my house is small and I already have an SP-600, so Hammarlund is well represented. As presently arranged, it will likely get recycled in a week or two, which I hate to see. If someone wants it, I can get it. It's located in Santa Rosa, California, about 50 miles north of San Francisco. I can fetch it to Sausalito, San Francisco, or the Berkeley area for free. I'd rather not ship it if I can avoid it. Price is free, but shipping certainly ain't if it comes to that. It's a pretty fancy one, like a junior SP-600 to my quick look. Takers? Regards, Scott ------------------------------ From: "Jack" To: Old Tube Radios Subject: Kansa City Boatanchorites Date: Sun, 14 Mar 2010 19:37:29 -0500 Message-ID: <005701cac3d7$b20e7f80$162b7e80$@net> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0058_01CAC3AD.C9387780" Content-Language: en-us This is a multi-part message in MIME format. ------=_NextPart_000_0058_01CAC3AD.C9387780 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit If there's anyone in the Kansas City area who REALLY builds things with vintage parts, let me know. .. I have to start cleaning out my 50-year collection of stuff....boxes of RF connectors, pilot lights, fuse holders, transformers, rack cabinets, and on, and on. I've got telephone equipment, wire/cable, two-way radio stuff, etc. I will GIVE the stuff to a legitimate boatanchor builder. I expect to have a Spring-cleaning open house some time in May. 73, Jack K0TTY K0TTY@arrl.net ------=_NextPart_000_0058_01CAC3AD.C9387780 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ---REMAINDER OF MESSAGE TRUNCATED--- * * This post contains a forbidden message format * * (such as an attached file, a v-card, HTML formatting) * * Mail Lists at theporch.com only accept PLAIN TEXT * * If your postings display this message your mail program * * is not set to send PLAIN TEXT ONLY and needs adjusting * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ------=_NextPart_000_0058_01CAC3AD.C9387780-- ------------------------------ Message-ID: From: "RICHARD GEORGE" To: Old Tube Radios Subject: Johnson Ranger parts needed Date: Mon, 15 Mar 2010 07:14:00 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit I need a function switch for a Johnson ranger transmitter. Help me restore this old classic. K6KWQ Dick Amps by "MORE POWER" ------------------------------ Message-ID: <28620573.1268703004883.JavaMail.root@elwamui-huard.atl.sa.earthlink.net> Date: Mon, 15 Mar 2010 21:30:04 -0400 (EDT) From: Richard Dillman To: Old Tube Radios Subject: See Denice in QST Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Our very own Ms. Denice Stoops is pictured on page 85 of the April edition of QST in an article on Straight Key Night. Look closely at the photo and you'll see that Denice is using her "flat iron" straight key that employs the sole plate of an electric iron as the base. The chrome Vibroplex with which she plied her trade as a brass pounder at NMC and KPH may also be seen. VY 73, RD ================================= Richard Dillman Chief Operator, Coast Station KSM Maritime Radio Historical Society http://www.radiomarine.org ================================= ------------------------------ Message-ID: From: "Allan Fritsche" To: Old Tube Radios Subject: Halli SX-62A Last for now Date: Tue, 16 Mar 2010 16:03:31 -0500 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit Well gang, Got all the paper caps replaced (42 of them) and decided to leave the extremely difficult 2 remaining for another day. These are both .047 rated at 200V and are used as RF cathode bypass in the two RF amp tubes. What a job, but the power transformer now runs at 120 degrees instead of the 160 I measured before starting. Mucho leakage was the problem there HI. Talk about a hot receiver, I have to run the sensitivity control down to about 3 to prevent overload on the broadcast band while listening to Rush. Please no comments. The usual cleaning up and cosmetic issues remain, but that's just elbow grease work. Definitely a keeper. If I run into any snags on the final alignment I will ask here. Well it's been fun and I hope we get some more restoration projects reported on. Good to hear from so many familiar names from the past. Your Friend Al in Sunny Houston W5ADF ------------------------------ Message-ID: <003101cac54e$0de4f470$869e480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: Re: Halli SX-62A Last for now Date: Tue, 16 Mar 2010 14:17:06 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit > .....These are both .047 rated at 200V and are used as RF cathode bypass in the two RF amp tubes. I wouldn't bother to replace them. They are shunted by cathode resistors and the capacitor's leakage at its worst is many orders of magnitude less than the current in the cathode resistor because the capacitor never sees more than a few volts. Arden Allen KB6NAX Adopt a shelter dog, save an innocent life, and make a friend forever =:-) ------------------------------ Message-ID: <21590895.1268778131403.JavaMail.root@elwamui-mouette.atl.sa.earthlink.net> Date: Tue, 16 Mar 2010 18:22:11 -0400 (EDT) From: spr@earthlink.net To: Old Tube Radios Subject: Re: Halli SX-62A Last for now Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Alan, I think your avc may not be working quite right if you need to use the RF gain control to prevent overload. Dumb question: are you sure the AVC switch is on? Could there be a resistor in that circuit that has aged *way* up? Does the S-meter respond normally? I ask because my SX-42 doesn't have this problem as far as I know. Regards, Scott -----Original Message----- >From: Allan Fritsche >Sent: Mar 16, 2010 5:03 PM >To: Old Tube Radios >Subject: Halli SX-62A Last for now > >Well gang, Got all the paper caps replaced (42 of them) and decided to leave >the extremely difficult 2 remaining for another day. These are both .047 >rated at >200V and are used as RF cathode bypass in the two RF amp tubes. What a job, >but >the power transformer now runs at 120 degrees instead of the 160 I measured >before >starting. Mucho leakage was the problem there HI. > >Talk about a hot receiver, I have to run the sensitivity control down to >about 3 to >prevent overload on the broadcast band while listening to Rush. Please no >comments. > >The usual cleaning up and cosmetic issues remain, but that's just elbow >grease work. >Definitely a keeper. >If I run into any snags on the final alignment I will ask here. > >Well it's been fun and I hope we get some more restoration projects reported >on. >Good to hear from so many familiar names from the past. > >Your Friend Al >in Sunny Houston >W5ADF > > > ------------------------------ MIME-version: 1.0 Content-type: multipart/alternative; boundary="Boundary_(ID_zG722+IZ2DpIC0Bj9NF48g)" Message-id: <4BA01439.8030605@ar88.net> Date: Tue, 16 Mar 2010 19:28:57 -0400 From: Al Klase To: Old Tube Radios Cc: Old Tube Radios Subject: Re: Halli SX-62A Last for now This is a multi-part message in MIME format. --Boundary_(ID_zG722+IZ2DpIC0Bj9NF48g) Content-type: text/plain; CHARSET=US-ASCII; format=flowed Content-transfer-encoding: 7BIT You should be able to run the RF gain wide open on AM under almost any conditions. Read my AVC harangue: http://www.skywaves.ar88.net/commrx/Maintenance/agc.htm There are mica coupling caps on the RF amp grids that may be leaky. Al On 3/16/2010 6:22 PM, spr@earthlink.net wrote: > Hi Alan, > > I think your avc may not be working quite right if you need to use the RF gain control to prevent overload. Dumb question: are you sure the AVC switch is on? Could there be a resistor in that circuit that has aged *way* up? Does the S-meter respond normally? > > I ask because my SX-42 doesn't have this problem as far as I know. > > Regards, > > Scott > > -----Original Message----- > >> From: Allan Fritsche >> Sent: Mar 16, 2010 5:03 PM >> To: Old Tube Radios >> Subject: Halli SX-62A Last for now >> >> Well gang, Got all the paper caps replaced (42 of them) and decided to leave >> the extremely difficult 2 remaining for another day. These are both .047 >> rated at >> 200V and are used as RF cathode bypass in the two RF amp tubes. What a job, >> but >> the power transformer now runs at 120 degrees instead of the 160 I measured >> before >> starting. Mucho leakage was the problem there HI. >> >> Talk about a hot receiver, I have to run the sensitivity control down to >> about 3 to >> prevent overload on the broadcast band while listening to Rush. Please no >> comments. >> >> The usual cleaning up and cosmetic issues remain, but that's just elbow >> grease work. >> Definitely a keeper. >> If I run into any snags on the final alignment I will ask here. >> >> Well it's been fun and I hope we get some more restoration projects reported >> on. >> Good to hear from so many familiar names from the past. >> >> Your Friend Al >> in Sunny Houston >> W5ADF >> >> >> >> > -- Al Klase - N3FRQ Jersey City, NJ http://www.skywaves.ar88.net/ --Boundary_(ID_zG722+IZ2DpIC0Bj9NF48g) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ---REMAINDER OF MESSAGE TRUNCATED--- * * This post contains a forbidden message format * * (such as an attached file, a v-card, HTML formatting) * * Mail Lists at theporch.com only accept PLAIN TEXT * * If your postings display this message your mail program * * is not set to send PLAIN TEXT ONLY and needs adjusting * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * --Boundary_(ID_zG722+IZ2DpIC0Bj9NF48g)-- --Boundary_(ID_zG722+IZ2DpIC0Bj9NF48g)-- --Boundary_(ID_zG722+IZ2DpIC0Bj9NF48g)-- ------------------------------ Message-id: <4BA024B4.7030308@ar88.net> Date: Tue, 16 Mar 2010 20:39:16 -0400 From: Al Klase MIME-version: 1.0 To: Old Tube Radios Subject: Re: Halli SX-62A Last for now Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit Sorry about the html post. Ignore the part about the coupling caps. I thought I was replying to Alan and his AR-88 on the RCA list not Allan and his SX-62 on this list. The rest is true. Al On 3/16/2010 7:28 PM, Al Klase wrote: > You should be able to run the RF gain wide open on AM > under almost any conditions. Read my AVC harangue: > http://www.skywaves.ar88.net/commrx/Maintenance/agc.htm > > > > There are mica coupling caps on the RF amp grids that may be leaky. > > > > Al > > > > > > -- Al Klase - N3FRQ Jersey City, NJ http://www.skywaves.ar88.net/ ------------------------------ Message-ID: <001901cac5fc$8210ccd0$6b9d480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: Re: Halli SX-62A Last for now Date: Wed, 17 Mar 2010 11:05:56 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Al mentioned the Hewlett Packard 410B VTVM for its high megohm resistance measuring ability on his page, http://www.skywaves.ar88.net/commrx/Maintenance/agc.htm. The last index mark before infinity indicates 500 megohms on the Rx1 megohm range. Well, that woke me up to the reality that I have about thirty (30+/-) 410B's in various conditions. Let me know if you are looking for a nice 410B or just a parts junquer. Prices very reasonable. Time to free up some living space for once.... Arden Allen KB6NAX Adopt a shelter dog, save an innocent life, and make a friend forever =:-) ------------------------------ Message-ID: <8AC947A8313042CEA70FE3348F8A70F9@boudreaux> From: "David Stinson" To: Old Tube Radios Subject: Recovering "Bumble Bee" Capacitors Date: Wed, 17 Mar 2010 13:47:06 -0500 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit At a recent hamfest, I bought a large bag of NOS Sprague .1 uFd, 400 volt "Bumble Bee" capacitors, the ancestors of the "Black Beauty" type, for $3. All of them were, of course, leaky to one degree or the other. I took a handful of the worst leakers and put them in the stove at 250 degrees for one hour. The cases split, of course, and a small amount of wax pooled under them. I let them cool overnight and checked them again. To my surprise, they check excellent! Every one of them came back. At full voltage, they are in spec for capacitence and leakage is less than 10-20 microamperes at 400 volts. Of course, with the cases split, they'll absorb water again. I'm thinking of resealing with liquid tape or the like. I have quite a few more of them left. Perhaps if I use a lower temp and longer time, I can "dry" them without splitting the cases. 73 Dave S. ------------------------------ Message-ID: <17560233.1268854652476.JavaMail.root@mswamui-backed.atl.sa.earthlink.net> Date: Wed, 17 Mar 2010 12:37:32 -0700 (GMT-07:00) From: spr@earthlink.net To: Old Tube Radios Subject: Re: Recovering "Bumble Bee" Capacitors Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Dave, Well, that's about 40 megohms DC resistance after baking. 10 uA in a 1 Meg grid leak makes 10V bias, enough to toast your 6V,F,K,or L6s nicely. Even 5V in a 500K grid leak is enough to upset an audio PA's operating point, and it will almost certainly cut off any earlier voltage amp stage. The little yellow caps we have all been using for some time measure about 50,000 megohms; Sprague orange drops measure over 500,000 megohms, the upper limit of my GR megger. These measurements are at 400V, as are yours. Interesting result, but, I fear, still not good enough for general service. Regards, Scott -----Original Message----- >From: David Stinson >Sent: Mar 17, 2010 11:47 AM >To: Old Tube Radios >Subject: Recovering "Bumble Bee" Capacitors > >At a recent hamfest, I bought a large bag of NOS Sprague >.1 uFd, 400 volt "Bumble Bee" capacitors, the ancestors of > the "Black Beauty" type, for $3. >All of them were, of course, leaky to one degree or the other. >I took a handful of the worst leakers and put them in the stove >at 250 degrees for one hour. The cases split, of course, >and a small amount of wax pooled under them. >I let them cool overnight and checked them again. >To my surprise, they check excellent! Every one of them >came back. At full voltage, they are in spec for capacitence >and leakage is less than 10-20 microamperes at 400 volts. >Of course, with the cases split, they'll absorb water again. >I'm thinking of resealing with liquid tape or the like. >I have quite a few more of them left. >Perhaps if I use a lower temp and longer time, >I can "dry" them without splitting the cases. > >73 Dave S. > ------------------------------ Message-ID: From: "David Stinson" To: Old Tube Radios Subject: Re: Recovering "Bumble Bee" Capacitors Date: Wed, 17 Mar 2010 15:41:17 -0500 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=original Content-Transfer-Encoding: 7bit ----- Original Message ----- From: Subject: Re: Recovering "Bumble Bee" Capacitors > Hi Dave, > > Well, that's about 40 megohms DC resistance after baking. 10 uA in a 1 Meg > grid leak makes 10V >bias, enough to toast your 6V,F,K,or L6s nicely. Even > 5V in a 500K grid leak is enough to upset an >audio PA's operating point, > and it will almost certainly cut off any earlier voltage amp stage. Thanks for writing, Scott and Bruce. Right after taking them out of the oven, when still hot, they leaked badly. I saw my results after a night in the cold. I ain't the brightest bulb here by any stretch, but I'm not ready to give up yet. Your senerio could be a concern, were the part of the circuit in which the caps were installed to be run at 400 volts, or if used as interstage coupling from a plate circuit at high B+ to a following stage. A bias circuit, AVC, tone circuit or cathode bypass is running at just a few volts. At under 40 volts or so, the leakage current is unmeasurable by my gear, but the capa. and ESR still look good. If used as bypasses, typical service would be around 250 volts. So far, the "cooked" caps are averaging about 8-9 microamps at that level, or the equiv. of about 2.8 megaOhms to ground, dissipation about 2 one-thousandths of a Watt. Not too bad for an old bypass. I think I'll play with them a little more. 73 Dave S. ------------------------------ Message-ID: <4D536531EE6A41E49C48B4CB58DC38E5@wilsonspc> From: "Wilson Lamb" To: Old Tube Radios Cc: "John Poulton" , "john Brewer" , "Al Parker" , , "Terry Rogers" , Subject: Silly Signal Shifter Saga Date: Wed, 17 Mar 2010 17:06:26 -0400 MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_NextPart_000_00CB_01CAC5F4.2D9B8760" This is a multi-part message in MIME format. ------=_NextPart_000_00CB_01CAC5F4.2D9B8760 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit This is going out to everyone (I think) who helped me with Shifter info or stories. No doubt Boatanchors will generate some dupes, sorry. If you don't want to hear any more about shifters, let me know. Well, I've reached a plateau, I think, after a slightly difficult climb. It wasn't hard to get the SS started, just new filter caps. Then the fun began. It seemed to be working (40m) into the dummy load, but when I fed it into my little MFJ tuner and the long wire, confusion started. I had a few watts output, but high (5+) swr, no matter how the tuner was set. Terry wisely suggested there might be harmonics going to the tuner, which would cause reflected power because they were not on the rig frequency, where the tuner was set. That was such a good idea I decided to put the scope on the output and "see what's happening". WOW, there was a lot of 3.5MHz coming through, even though the 6L6 was supposed to be doubling. At various tuner settings, I could get more or less 3.5 energy, but the scope often showed bizarre waveforms, making me not want to go on air! Looking at the plate of the 6L6 and the output on the link were equally discouraging. I messed with that problem quite a bit, even reading up on doublers to see if there were tricks I'd forgotten, or even never known. I then determined that the grid of the 6L6 doubler was not being driven very hard. I had adjusted the oscillator plate tuning on another and and thought it would be OK on 40, but, guess what, it was WAY off. When I peaked it I had a couple mA of grid current to the 6L6 and much more output! Still, the output waveform did not look good and it changed radically with adjustment of the tuner, now feeding a dummy load. I checked the output tuning of the 6L6 and found it to be very broad. I could get no dip when coupling a Grid Dipper to the plate tank of the 6L6. I took the dummy load loose, found a strong dip, and set the tank to the low end of 40m. Things looked better, but I still had the bizarre waveforms. I connected the tuner and end fed antenna, but there was little difference in the scope views. It finally hit me that I was being really dumb and that I was seeing reflected energy coming back from the tuner, which added to the outgoing signal and made the weird scope pictures. When I moved the scope probe near the antenna, to look at the signal getting through the tuner, I got a fine picture of 40m RF! Not strong but quite clean and at 40m! The last hurdle was a serious chirp. I found that when the output was peaked there was a LOT of chirp, far too much for even CX use. It was due to the 6L6 grid loading the osc and pulling it off frequency! When I detuned the osc plate tank until I lost 10-15% of the output, I also lost the chirp. It's clear that the electron coupling of the osc (The osc is the grid of the 6F6, electron coupled through the screen to the plate.) is not good enough isolation to prevent loading. So here I am, on the air. I've made several QSOs as far away as MI, OH, NJ. I still show a high SWR, which I don't yet understand, and I don't know the output power because the tuner probably doesn't read properly at high SWR. The output link is six turns, on a sixteen turn coil, so I think that's part of the problem. They did not design for 50 Ohms. I'm going to whip two or three turns on there and see if it behaves differently. That's probably enough time spent on a 1942 VFO that I won't use much! Hopefully I'll find some coils or get the energy to wind some before long, but that's about it for the Signal Shifter. Actually, 80m may be the only other band I try, but maybe 20, who knows. I'll build a driver stage so the SS can drive my old wooden chassis final and that will be that for a while too. The driver chassis is already in the rack, so it won't be much trouble. I'd like to use an 801, but Ebay audiophools have driven their price to unreasonable levels. Maybe an 807, but I'd hoped to stay with mid 30s triodes... Please let me know if you have Shifter lore, literature, or problems to share. I'd like to find out the values of all the tuning caps, which are not in the book, but I sure don't want to set up to measure them! And I'm still really wanting an original 1938 version, to be a closer age match to the old rig. Also let me know if you want off this list. I know you may have better things to do than read about shifters! I'll issue an update when something big happens, like getting the big final going or solvint the SWR mystery. 73, Wilson W4BOH ------=_NextPart_000_00CB_01CAC5F4.2D9B8760 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ---REMAINDER OF MESSAGE TRUNCATED--- * * This post contains a forbidden message format * * (such as an attached file, a v-card, HTML formatting) * * Mail Lists at theporch.com only accept PLAIN TEXT * * If your postings display this message your mail program * * is not set to send PLAIN TEXT ONLY and needs adjusting * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ------=_NextPart_000_00CB_01CAC5F4.2D9B8760-- ------------------------------ Message-ID: From: "David Stinson" To: Old Tube Radios Subject: Re: Recovering "Bumble Bee" Capacitors Date: Wed, 17 Mar 2010 19:11:25 -0500 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=response Content-Transfer-Encoding: 7bit >> ......I think I'll play with them a little more. > Following what Scott said you are wasting your time... I dunno.... the guitar guys like these things even when they're darn near shorted; Don't ask me why. They want them and they have their reasons, I guess. Here's an interesting thing: I toasted another handful at 160 degrees for an hour. With one exception, the cases did not split and they did not leak wax. I didn't expect much improvement, but was quite surprised. These caps were way beyond what I'd try anywhere, all over 1 mA. One even leaked at 5 mA+. With the one exception of the case splitter, they are now 100 microAmps or less. Two are less than 10 microAmps. I wonder.... Since the cases did not split, and it's possible that the core temp of the caps didn't get to the full 160 degs in only an hour, is it possible that the problem is not with the paper at all, but something to do with the Bakelite? I've already proven that Bakelite will absorb water and it can be driven out with heat; I free-up those large PL-** connectors that way all the time, and it's the Bakelite shrinking, not the metal expanding, because they stay freed-up after cooling. Afterall- Dr. Barry isn't going to be wrong. If acidified, rotted paper isn't recoverable, than my treatment should not have improved them so markedly. Yet it did. And if it the paper can't be recovered, yet these caps *are* recovered, than it isn't the paper. Getting more interesting all the time ;-). I'm going to leave a few of them at 250 volts for a couple of days and see what happens. 73 Dave S. ------------------------------ End of BOATANCHORS Digest 4324 ******************************