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Ralph Mowery <rmowery28146@earthlink.net>: Apr 30 10:37AM -0400 I am in the US and just doing my own repairs and building.   Do I need to use any of the lead free solder to repair the boards that were made usign the lead free solder?   I have not bought any yet and have been practicing witht he SMD on old computer boards. That stuff seems a pain to work with compaired to the 'regular' tin/lead that I have been using for the last 50 years.   I have been thinking about getting some for the power transistors and resistors where there is a lot of heat build up but not sure if that application would even be worth the trouble.

N_Cook <diverse@tcp.co.uk>: Apr 30 04:23PM +0100 On 30/04/2016 15:37, Ralph Mowery wrote:   > I have been thinking about getting some for the power transistors and > resistors where there is a lot of heat build up but not sure if that > application would even be worth the trouble.   If you are just doing repairs or mods to PbF stuff then use SAC (Tin +Silver+Copper) solder, the cost would be prohibitive for complete new build soldering.

Ralph Mowery <rmowery28146@earthlink.net>: Apr 30 11:38AM -0400 In article <ng2iej$oba$1@dont-email.me>, diverse@tcp.co.uk says...   > If you are just doing repairs or mods to PbF stuff then use SAC (Tin > +Silver+Copper) solder, the cost would be prohibitive for complete new > build soldering.   As I would not use a pound every few years, the cost would not be a problem for me. For the very small solder I doubt I would use a pound of the lead free solder for the rest of my life.   As it is just for my own use at home I am not worried about the legal Rohs part.   While the above seems like dumb questions, I find it is easier to ask than spend all day looking for the answers.   I did see where some of the water clean up flux says that it can be left on and some of it says it is safe for a few dys so I am going to stay away from that. Reminds me of the old acid flux. May be ok to use if cleaned off, but absolutly can not be left on if used. Even then I wold never use it on anything but pumbing.

Fred McKenzie <fmmck@aol.com>: Apr 30 12:47PM -0400 In article <MPG.318e8d38c906088989694@news.east.earthlink.net>,   > I have not bought any yet and have been practicing witht he SMD on old > computer boards. That stuff seems a pain to work with compaired to the > 'regular' tin/lead that I have been using for the last 50 years.   Ralph-   I sympathize!   The problem with using tin-lead solder with SMD, is that lead "amalgamates" with the silver contacts of surface mount devices, resulting in a non-conductive layer between the device and the circuit.   While tin-lead-copper solder may help, it would be better to use lead-free. It may work better if you use a temperature-controlled iron, capable of higher temperatures than your old iron.   Fred

N_Cook <diverse@tcp.co.uk>: Apr 20 11:26AM +0100 On 20/04/2016 08:46, Gareth Magennis wrote:   > Gareth.   Somewhere along the way this amp has acquired 2 printed pages of the G class PA, presumably someone accessed from Peavey as I cannot find it out in wwwland for a clearer image, useable images but should have been printed out as 4x A4 as some fine details is lost . pages titled Mixer amp 600 watts A, and internal doc number 99099390

N_Cook <diverse@tcp.co.uk>: Apr 30 11:37AM +0100 eventually found the user manual , for this ferret thing http://peavey.com/media/pdf/manuals/xr684fand696f_manual.pdf

Ralph Mowery <rmowery28146@earthlink.net>: Apr 29 07:27PM -0400 Does the flux in solder really get old ?   I have some of the older 60/40 flux core that is over 20 years old and never had any problems with it.   Just getting into the SMD soldering and the tubes of solder paste have an expiration date on them of about a year and some want to be kept in the refrigerator when not being used. Also bought some liquid flux and it mentions an expiration date about a year or so later.   Just being a home user it may take me years to use the stuff. I know lots of things have an expired or use by date on them,but that does not really mean much. I think the government just requires a date on some items.

Ian Malcolm <See.My.Sig.for.email@totally.invalid>: Apr 29 11:46PM > an expiration date on them of about a year and some want to be kept in > the refrigerator when not being used. Also bought some liquid flux and > it mentions an expiration date about a year or so later.   The problem with solder paste is surface oxidisation of the very small particles of solder in it, and possibly saponification of the flux due to its reaction with the oxidised solder. Keep it refrigerated in a ziplock bag or hermetically sealed container with a silica gel sachet to control humidity, at the lowest possible storage temperature as the rate of degradation doubles with every 10 deg C increas in temperature, and allow it to warm to room temperature an hour before use.   Fluxes are a more complex matter. Liquid Rosin fluxes are unlikely to degrade over decades if securely stoppered. Liquid Synthetic fluxes may be more problematic and if any component can further polymerise, the expiry date may be justified. If kept cool and well stoppered, in a dark place or opaque bottle, the chances are that it will still be good well after the expiry date. Gel fluxes may be stable or may tend to seperate or degrade. Again, cool and dark may help.   Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED) ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL

Michael Black <et472@ncf.ca>: Apr 29 11:24PM -0400

N_Cook <diverse@tcp.co.uk>: Apr 30 08:41AM +0100 On 30/04/2016 00:27, Ralph Mowery wrote: > lots of things have an expired or use by date on them,but that does not > really mean much. I think the government just requires a date on some > items.   A pot of solder "paste" (pretty solid now) I use, is expiry dated 1996, I just locally mix in a blob of flux to make a small amount useable each time

Ian Malcolm <See.My.Sig.for.email@totally.invalid>: Apr 30 05:12AM dansabrservices@yahoo.com wrote in > apply the Chip-Quik. This with a little heat should allow for easy > removal.   > Dan   +1. Chip-Quik will get the melting point of the remaining solder down to around 100 deg C so you can keep all 28 joints molten with a hot air gun on a fairly low temperature setting without cooking the board.   -- Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED) ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL

David Lesher <wb8foz@panix.com>: Apr 30 03:17AM >I would really like a very small, cheap, air tank that I can charge every >now and again at the local garage (i.e. can be filled with a standard car >tyre pump).   Harbor Freight sells small pancake compressor+tank setups. Item # 60637, Item # 95275   When on sale, it can be ~$40, as I recall. When it runs out of air, you add some electricity and make more.     -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

John Robertson <spam@flippers.com>: Apr 19 08:35PM -0700 > enough. I have come across write only memory DVDs and that's what I > use my DVD rewinder for. > Eric   WOM is not that rare - the 25120 was designed by Signetics engineer John G 'Jack' Curtis back in the early 70s and included in their catalog:   http://www.repeater-builder.com/molotora/gontor/25120-bw.pdf   John ;-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Heisenberg <Barry@saymyname.com>: Apr 20 01:55PM +1000 >enough. I have come across write only memory DVDs and that's what I >use my DVD rewinder for. >Eric   I have a camcorder that uses standard beta cassetes.   =-=- "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (*Diagnostic and Statistical Manual of Mental Disorders)

Jeff Liebermann <jeffl@cruzio.com>: Apr 19 09:13PM -0700 On Tue, 19 Apr 2016 20:35:56 -0700, John Robertson <spam@flippers.com> wrote: >G 'Jack' Curtis back in the early 70s and included in their catalog: >http://www.repeater-builder.com/molotora/gontor/25120-bw.pdf >John ;-#)#   I was one of the winners in the applications contest. I later tried to specify a WOM in a design: <http://www.sigwom.com/?page_id=57> <http://ba.internet.narkive.com/Y3r0WXMC/ot-signetics-wom-hey-jeff-liebermann>   -- 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 19 09:45PM -0700 >THEY CAME IN AN ANTI STATIC BAG !   Anti-static bags don't work. I put one of my radio designs inside such a bag and all I heard out of the speaker was the same old static.   I like the DVD rewinder, but can't you just insert the CD upside-down and play it again to rewind it?   You really need anti-static bags for protecting clip leads. Atmospheric electricity increases at the rate of about 30 volts/ft[1]. If you're 6ft tall, there should be 180 volts between your head and your toes. If you bridge this voltage with one of your new clip leads, it will surely create a spark. With the typical low quality of Chinese clip leads, that would probably blow the wire as if it were a fuse.     [1] <https://en.wikipedia.org/wiki/Atmospheric_electricity> "...the potential, aka 'voltage', increases with altitude at about 30 volts per foot (100 V/m)..."   -- 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

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