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Michael Black <et472@ncf.ca>: Apr 03 12:10AM -0400

avagadro7@gmail.com: Apr 11 05:46PM -0700 well, bought a 140/100 watt gun and tips. The standard tips fell apart at the tip. As if the tips were soldered together. Very funny HaHa.   Is there a heavier duty tip for the 140/100 watt gun ?   I used one in HS that would blow a hole thru the fridge door. This gun is not that. Nor did I experience tip failure.   opinions ?

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 11 09:01PM -0400 > I used one in HS that would blow a hole thru the fridge door. This > gun is not that. Nor did I experience tip failure.   > opinions ?   The Weller 8200 isn't much use IMO. I have its big brother, the D550, which I use for making FR4 shield boxes, soldering to brass or copper stock, that sort of stuff.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

"Ralph Mowery" <rmowery28146@earthlink.net>: Apr 11 11:12PM -0400 <avagadro7@gmail.com> wrote in message news:5df119f6-658d-4e34-8483-6f86cf28d0c3@googlegroups.com...   > I used one in HS that would blow a hole thru the fridge door. This gun is > not that. Nor did I experience tip failure.   > opinions ?   I doubt the gun would do that. I have one that I got about 50 years ago and another. I also have two others that each one is higher rated than the other.   There are two types of tips that I know of for soldering. One is copper and the other is silver color. Then there is a tip made for cutting plastic that has a wide flat on the end. There may be more. I am thinking of a silver colored one that comes out to the end and wraps around that does not have the buldge on the end and is flat at the end, but could be wrong about that one.   The only times I have had the tips fall apart is after a lot of usage.

Jeff Liebermann <jeffl@cruzio.com>: Apr 11 08:49PM -0700 >well, bought a 140/100 watt gun and tips. The standard tips >fell apart at the tip. As if the tips were soldered together. >Very funny HaHa.   I've done that by tightening the nuts which twists the copper tip wire. When it gets hot, the wire softens a little, causing it to break. I've also done that by "pushing" on the tip, causing the wires to spread and eventually break.   Hmmm... You said "tips". Duz that mean you destroyed more than one? What were you doing to make that happen?   >Is there a heavier duty tip for the 140/100 watt gun ?   The standard soldering tip is the 7135 and variations. <http://www.acehardware.com/product/index.jsp?productId=1289816> Heavy duty (premium) soldering tip is 8125 and variations. <http://www.acehardware.com/product/index.jsp?productId=1289817> Make sure you don't get a tip made for the D550 or D650.   Or, if you're a cheap tightwad penny pincher, roll your own: <http://www.instructables.com/id/Free-Replacement-Tip-for-Soldering-Guns/>   >I used one in HS that would blow a hole thru the fridge door. >This gun is not that. Nor did I experience tip failure.   Other than for cutting plastic rope, I don't see the soldering gun to be very useful these daze. I would not use a gun to repair any manner of electronics on a PCB. May I suggest you invest in a soldering iron instead?   >opinions ?   Find a cheap replacement tip and sell it and the gun. Buy a soldering iron and some desoldering tools. More free advice after you disclose what you're trying to solder/unsolder/destroy.       -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

isw <isw@witzend.com>: Apr 11 09:15PM -0700 In article <5df119f6-658d-4e34-8483-6f86cf28d0c3@googlegroups.com>,   > I used one in HS that would blow a hole thru the fridge door. This gun is not > that. Nor did I experience tip failure.   > opinions ?   I have been using properly shaped lengths of #12 copper wire as tips for my Weller for years. True, they don't last as long, but they are a whole lot less expen$ive than the "real thing". At first use, heat a new tip slowly and carefully (so it won't oxidize), and tin it quickly but thoroughly.   Isaac

Jeff Liebermann <jeffl@cruzio.com>: Apr 11 09:58PM -0700 >lot less expen$ive than the "real thing". At first use, heat a new tip >slowly and carefully (so it won't oxidize), and tin it quickly but >thoroughly.   You might try plating iron onto the copper wire: <http://www.finishing.com/379/18.shtml> I haven't tried this, mostly because I don't need it, but it does look like one can make a somewhat better tip with this method.   If you want longer life, there's nickel, on tungsten-cobalt, on copper: <http://www.google.com/patents/US3080842>       -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Michael Black <et472@ncf.ca>: Apr 12 12:26AM -0400

Jeff Liebermann <jeffl@cruzio.com>: Apr 11 02:36PM -0700 >>My guess(tm) is that the plastic in the phone is probably ABS (acrylic >>butyl styrene) which will weld nicely with acetone solvent.   >ABS=Acrylonitrile butadiene styrene.   Sigh. I stand corrected (again). Thanks.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Apr 11 03:28PM -0700 >the stuff. I think. See the link: >http://www.homedepot.com/p/Loctite-0-85-fl-oz-Plastic-Epoxy-1360788/100371824 >Eric   Do you recall if the goo you used took 5 min or 20 min to set?   The Home Despot ad above shows "Epoxy Plastic" with a 5 minute time to set. However, I couldn't find that on the Loctite web pile, but found this instead: <http://www.loctiteproducts.com/p/epxy_plstc_s/overview/Loctite-Epoxy-Plastic-Bonder.htm> which is a "Plastic Epoxy Bonder" with a 20 minute time to set. I prefer the longer setting times and overnight hardening, so I'll start with the 20 min flavor.   The Plastic Epoxy Bonder stuff is NOT an epoxy. Epoxy is a thermosetting plastic. The Plastic Epoxy Bonder is an acrylic, which is thermoplastic. See first question at: <http://juxtamorph.com/difference-between-polyester-acrylic-and-epoxy-resins/> That's fine because an acrylic based glue is what you want for ABS anyway.   I suspect it also has some sort of solvent to soften the base plastic. Looks like the formulation has changed slightly: <http://henkelconsumerinfo.com/products/henkel.datasheets.DownPdf.pdf?BUSAREA=0006&VKORG=3450&MATNR=1442491&RECNDH=20257403&ACTNDH=0&LANG=EN&COUNTRY=US> <http://www.menards.com/msds/107040_001.pdf> (older) Yep, 1% carbon tetrachloride solvent, which should do nicely for softening plastics. Three different forms of methyl methacrylate (MMA). Incidentally, MMA was once used for fake finger nails, but was banned for some reason: <http://www.hooked-on-nails.com/mmaandyou.html> I'm not sure what the other stuff does and am too lazy to dig it out.   So, what you have here is an acrylic plastic glue, with some rubber compound added to make it a little flexible, no epoxy resin anywhere in sight, and a bit of solvent to soften the base plastic. Also see the data sheet at: <http://www.loctiteproducts.com/tds/EPXY_PLSTC_S_tds.pdf>   The 5 min "Epoxy Plastic" MSDS is rather cryptic: <http://henkelconsumerinfo.com/products/henkel.datasheets.DownPdf.pdf?BUSAREA=0006&VKORG=3450&MATNR=1071291&RECNDH=20924077&ACTNDH=0&LANG=EN&COUNTRY=US> <http://henkelconsumerinfo.com/products/henkel.datasheets.DownPdf.pdf?BUSAREA=0006&VKORG=3450&MATNR=1071250&RECNDH=21213716&ACTNDH=0&LANG=EN&COUNTRY=US> and only shows "epoxy resin, proprietary". The hardener is listed as "tertiary amine" which is an epoxy resin curing agent.   I would go for the 20 minute flavor.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

etpm@whidbey.com: Apr 11 04:10PM -0700 On Mon, 11 Apr 2016 15:28:32 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >and only shows "epoxy resin, proprietary". The hardener is listed as >"tertiary amine" which is an epoxy resin curing agent.   >I would go for the 20 minute flavor. I don't remember if the stuff was 5 or 20 minutes but I suspect it was the 5 minute variety. I wondered about that epoxy name. Looking at the ingredients made me think it wasn't an epoxy but I don't know enough about epoxies to tell. I do know that there are some pretty damn good acrylic based adhesives though. I suspect that the adhesive backed aluminum tape made for ductwork (not duct tape!) uses an acrylic based adhesive. That stuff sticks remarkably well and does so for years. Eric

Bennett <bjprice@cal.berkeley.edu>: Apr 11 05:12PM -0700 While it admits to not addressing the fine points of gluing all the different sorts of plastics, this web site is often really handy: www.thistothat.com     On 4/10/2016 1:12 PM, J. B. Wood wrote:

DaveC <not@home.cow>: Apr 11 11:05PM -0700 > I don't know what kind of plastic your part is but there is a two part > plastic cement that bonds well to many of the plastics that are hard > to glue. I don't remember the name   I've had great success mending most plastics of all kinds (varying degrees with poly-types) using Devcon Plastic Welder:   http://www.amazon.com/Devcon-22045-Plastic-Welder-Dev-Tube/dp/B003NUGL9S   It's my go-to solution when fixing anything plastic.   Cool phone. Brings back memories. Ours was (at different times, replacements installed after family of 6 abused it) red, yellow, black, white. With extra-long handset cord, of course.   Good luck.

DaveC <not@home.cow>: Apr 11 11:44PM -0700 History of the development of the Model 500 phone:   https://en.wikipedia.org/wiki/Model_500_telephone   Fascinating...

"pfjw@aol.com" <pfjw@aol.com>: Apr 09 04:14PM -0700 On Saturday, April 9, 2016 at 5:51:09 PM UTC-4, ohg...@gmail.com wrote:   A few things:   a) After a certain basic level of quality construction, a cap is a cap is a cap. So, within the universe of film caps, after that level, there is effectively nothing to choose between brands. Similarly within the universe of electrolytic caps.   b) at less than 5uF, moving from electrolytic caps to film caps is generally a good thing. Keep in mind that a typical electrolytic cap has a tolerance of -20% to +100% unless screened. The typical film cap (these days) is usually within 5% or less. So, a film cap will be far closer ab initio, and also stay that way. Above 5%, you may run into real-estate problems, so make sure the film cap will fit before making a purchase.   c) Voicing Reasons: Not really. Supply availability is far more likely and/or actual tolerance.   d) Better to 4.7 than 3.3. The 3.3 is at the bottom end of the electrolytic tolerance scale, 4.7 is close enough on the upper end.   e) Make your voltage *AT LEAST* 20% higher than OEM. Try to be "not more" than 100% if possible. Much more an issue with electrolytic than with film caps. I stock film caps in 200 (anything less than 100V) and 600/650V (anything above to 550V).   Enjoy! That is a fine unit! Fisher iron is legendary.   Digikey is a fine source, also Mouser and Newark. All three will sell you quality goods.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Apr 09 11:12PM -0700 > And since 4uf caps are pretty much made of unobtainium, should I go > to 4.7 or 3.3, or should I cobble some together?   ** Just use any brand name 4.7uF, 63V electros.   Panasonic, Nippon-Chemicon etc.   IMO, 1960s Germanium transistor amplifiers are the "missing link" between tube and modern solid state - and they should stay missing.       .... Phil     .... Phil

"pfjw@aol.com" <pfjw@aol.com>: Apr 10 06:56AM -0700 On Sunday, April 10, 2016 at 2:12:28 AM UTC-4, Phil Allison wrote:   > IMO, 1960s Germanium transistor amplifiers are the "missing link" between tube and modern solid state - and they should stay missing.   OK - a valid opinion. On the other hand, this particular unit does use transistors that are still readily available, so a worthwhile bit of history for all that.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Apr 10 08:25PM -0700 > OK - a valid opinion. On the other hand, this particular unit does use > transistors that are still readily available, so a worthwhile bit of > history for all that.   ** You must have a different idea of "readily available" to mine.   The original RCA 35144s PNP outputs are not easy to find ( no listings on Ebay) and the only similar type I can find from a dealer is the AD149.     http://www.transparentsound.com/transistors/vintage-transistors/mullard/AD149M-0A.JPG     ... Phil

"pfjw@aol.com" <pfjw@aol.com>: Apr 11 05:38AM -0700 On Sunday, April 10, 2016 at 11:25:43 PM UTC-4, Phil Allison wrote:   > The original RCA 35144s PNP outputs are not easy to find ( no listings on Ebay) and the only similar type I can find from a dealer is the AD149.   > http://www.transparentsound.com/transistors/vintage-transistors/mullard/AD149M-0A.JPG   > ... Phil   Didn't suggest they were cheap, just readily available.   https://octopart.com/nte179-nte+electronics-22547   The NTE (by direct experience) is a drop-in replacement for the OEM in actual function. Or so it worked for me on a vintage KLH product back in the day. That amp is still working, as it happens.   I also agree that in the US, we have access to a much greater array of relatively local (2 days by cheap mail) suppliers than many other parts of the world.   Would I spend US$100 restoring this amp? Not for me, but given the cult status of vintage Fisher in the US, perhaps for that market.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Apr 11 07:23AM -0700 > Didn't suggest they were cheap, just readily available.   ** Then you are wrong on both counts.     > https://octopart.com/nte179-nte+electronics-22547   ** The NTE179 is nothing like the original RCA part and is very expensive.   OTOH, the AD149 is very close as sells for under US$10 on Ebay or just over A$5 from the store I usually frequent here in Sydney.       .... Phil

ohger1s@gmail.com: Apr 11 06:21PM -0700 On Sunday, April 10, 2016 at 2:12:28 AM UTC-4, Phil Allison wrote:   > Panasonic, Nippon-Chemicon etc.   > IMO, 1960s Germanium transistor amplifiers are the "missing link" between tube and modern solid state - and they should stay missing.   > .... Phil   Heheh... funny.   Phil: is your objection to 60s germanium amplifiers their performance, quirkiness, or parts availability (or all three).   Peter: none of the outputs are blown, so I don't need to acquire any ge for now, although I wouldn't mind picking up a set just to have. It is a very handsome and flexible amplifier if nothing else.   After doing some resistance checks around the output transistor, it's surprising that the outputs didn't blow. The bias controls read between 15 and 20 ohms before I marked their exact position and cleaned them. Once cleaned, lubed, and put back on the spot, they averaged about 6 ohms (and they're shunted by 22 ohm resistors). In the manual I have, there is a note about replacing the 22 ohm resistors with 10 ohm ones. Apparently, the bias pots may have been problematic from early on. The note also said to replace all four pots if suspect. Since the manual is of the same year as the amp, it tells me something about them. Perhaps those inert coupling caps prevented the output stage from blowing.

mittra@juno.com: Apr 10 09:17AM -0700 Thank you very much. All the links look promising.   The LED Supply link has a luminous intensity of 20 mW. I am not sure if this is same as Irradiance, which I need to be 220 mW/sr.   Nonetheless, both Jameco and LED supply are good sources and I will explore more.

"pfjw@aol.com" <pfjw@aol.com>: Apr 10 10:07AM -0700 > Thank you very much. All the links look promising.   > The LED Supply link has a luminous intensity of 20 mW. I am not sure if this is same as Irradiance, which I need to be 220 mW/sr.   > Nonetheless, both Jameco and LED supply are good sources and I will explore more.   Well, you have this one, with an irradiance of 550mW/sr, more than you need at a princely $0.36 each.   http://www.mouser.com/Search/ProductDetail.aspx?qs=VcOkZLzzaubOJpq6Xyji1A%3d%3d   Peter Wieck Melrose Park, PA

bitrex <bitrex@de.lete.earthlink.net>: Apr 09 04:29PM -0400 The "new" LCD display came out pretty nice if I do say so myself - replaced filter cap in the inverter, changed the contrast resistor on the board (stock one made the new display too dim), removed the reflective backing on the replacement display. Looks very 80s:   http://imgur.com/EsjRgv1

mogulah@hotmail.com: Apr 09 12:10PM -0700 > As far as I know this is just a "dumb system. How could it know that > the other party hung up and then to release the line. I seriously > doubt that they had the technology to do this in 1975.   I remember I was watching an old "Columbo" detective movie called "Death Lends A Hand" (1971) where the guest star "Robert Culp" kept bragging about how much better private investigative organizations were at (what was I guess) highest-end listening device technology than the police dept was.

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