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"Gareth Magennis" <soundserviceleeds@outlook.com>: Jul 26 06:55PM +0100 "N_Cook" wrote in message news:nn7dmg$m4$1@dont-email.me...   As though a thermal protect measure is cutting in falsely, but all valve. 10 minutes at gig level, longer at practise level, initially looses bass and then over a couple of minutes vol drops to uselessly low. Switch off ,cool down, and fine again. I'll check with a variac, to simulate gradual loss of DC, but is that the symptom sequence of loss of DC to a valve amp, lose bass then lose vol. Valves have been swapped out , but not the rectifier bottle, likely suspect?, a saggy 2x4007 lump will go in there initially to check that. A hot-air gun looks a promising tool. No hum reported, unlikely a major cap problem,a minor cap problem, surely not a Tx problem               You could check it is not a dry jointed heater connection to one or more valves.     Gareth.

Phil Allison <pallison49@gmail.com>: Jul 26 08:42PM -0700 Gareth Magennis wrote:   > You could check it is not a dry jointed heater connection to one or more > valves.   ** I have seen any number of Russian and Chinese octal valves with badly soldered pins - the steel wires inside the hollow pins are dry jointed and can disconnect at whim. This is visible under magnification.   If this happened on heater pins ( 2 or 8 in a GZ34 ) the output would fade down to nothing over about 10 seconds. A high resistance, intermittent connection could produce the symptoms seen by the OP.   Variations in the two spots of red light at the top of the valve would give you a big clue as well.     .... Phil

jurb6006@gmail.com: Jul 26 11:32PM -0700 >"** I have seen any number of Russian and Chinese octal valves with >badly soldered pins - the steel wires inside the hollow pins are dry >jointed and can disconnect at whim. This is visible under >magnification."   I never saw this, but then maybe I never looked. One of the things to know is what you don't know. I know I have had tubes with intermittent elements, but it is too late to think back to all of them that were octal.   Becoming inoperative could be caused by any pin and will be a malfunction of course, I mean the screen grid, plate, whatever.   If a tube/valve has good emission and all that but is intermittent, I wonder if that base would withstand a quick dip in a solder bath.

jurb6006@gmail.com: Jul 26 11:33PM -0700 >"** I have seen any number of Russian and Chinese octal valves with >badly soldered pins - the steel wires inside the hollow pins are dry >jointed and can disconnect at whim. This is visible under >magnification."   These are newer ones that are lead free ?

N_Cook <diverse@tcp.co.uk>: Jul 27 08:30AM +0100 >> "** I have seen any number of Russian and Chinese octal valves with >badly soldered pins - the steel wires inside the hollow pins are dry >jointed and can disconnect at whim. This is visible under >magnification."   > These are newer ones that are lead free ?   I'd forgotten about the bad solder problem , internal to the hollow pins of such bases, combined with PbF solder presumably as this is the original valve in a 2007 amp with green RoHS sticker on the back. I was only thinking of failed spotwelds internally. BTW mistyping of heading, model 1962 reissue with FET1 tremolo gizmo

N_Cook <diverse@tcp.co.uk>: Jul 27 08:42AM +0100 I tested this JJ GZ34S (no other info on it like date) and came up 2x 75% so good. I'll retry while applying hot air and vibrating it with my modded engraver tool (nylon bolt instead of active steel engraver pin) How to explore the internal solder of the hollow pins without disturbing the join between bakelite and glass at the base?

"pfjw@aol.com" <pfjw@aol.com>: Jul 27 05:43AM -0700 On Wednesday, July 27, 2016 at 3:42:38 AM UTC-4, N_Cook wrote:   > How to explore the internal solder of the hollow pins without disturbing > the join between bakelite and glass at the base?   Been doing this repair since 1978...   Touch a very hot iron to the pin, about midway between the point and the base. Hold for a few seconds. That should remelt the solder inside and reset the connection.   One of the few legitimate uses for a 200W soldering gun - be sure to pre-heat first. The idea is to get the pin hot enough to reflow the solder before the base knows what hit it. It is too little heat for too long a time that does damage.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Jul 27 02:00PM +0100 > One of the few legitimate uses for a 200W soldering gun - be sure to pre-heat first. The idea is to get the pin hot enough to reflow the solder before the base knows what hit it. It is too little heat for too long a time that does damage.   > Peter Wieck > Melrose Park, PA   I was thinking grind a small hole in each pin, introduce flux and ordinary soldering iron. Made up an adaptor (2 back to back QM connector pins , 1 male,1 female for each extender) to set the valve on Avo CT160 tester, raised up, so I can selectively hot-air heat the pins to see if failure recurs, then try resoldering the internal tail wires to the tube pins

Phil Allison <pallison49@gmail.com>: Jul 27 07:19AM -0700 > Been doing this repair since 1978...   ** Which is long before Pb free solder or Chinese and Russian made tubes became the norm - so completely irrelevant.   IME, the solder is cracked near the end of the pin and that is the only place solder is ever applied.   A little flux, some 60/40 solder and a hot iron tip is all that it takes to effect repair - plus a pair of working eyeballs.     .... Phil

"Ian Field" <gangprobing.alien@ntlworld.com>: Jul 26 09:54PM +0100 Originally W10 upgrade on W7 - that fell over after about a month.   A clean ground up install isn't much better...................   When W10 imploded - I couldn't repair, re-install or anything. The only cure was to overwrite the HDD by installing Linux, then clear all that out and start over with W10.   Pretty much every application starts off; "not responding", the HDD activity light is busy almost all the time. The cursor frequently changes from an arrow to a little blue circle, either way the response is usually hesitant - if it gets around to moving at all.....................   It was tolerable when I was using freeAVG, someone told me that was the cause of the problems and I should switch to Avira - I did that and now the PC is pretty much unuseable.   When I tried to go back to AVG, the installation failed, so it looks like I'm stuck with Avira.   Thanks for any help.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jul 27 06:55AM +1000 On 27/07/2016 6:54 AM, Ian Field wrote:   > When I tried to go back to AVG, the installation failed, so it looks > like I'm stuck with Avira.   > Thanks for any help.   **Well, I've been using Windows 10 on a laptop since November 2015. It is an i5 with 8GB RAM, a standard 1TB HDD. It boots in less than 30 seconds and responds MUCH faster than my desktop PC, which uses an old i5 processor, 16GB RAM and a 256GB SSD, running Win7. So far, Windows 10 seems to be just fine. Stable, fast and slightly more cumbersome than Win7, but I can get used to it.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Ian Field" <gangprobing.alien@ntlworld.com>: Jul 26 10:22PM +0100 "Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message news:dvq16nFh0l6U1@mid.individual.net... > processor, 16GB RAM and a 256GB SSD, running Win7. So far, Windows 10 > seems to be just fine. Stable, fast and slightly more cumbersome than > Win7, but I can get used to it.   So far - I'm thinking bad caps in the PSU or a virus got in when I burned the install disk .ISO   Starting over on a completely cleansed HDD didn't improve matters much, but a dodgy PSU should've gone tits up by now......................................   It had been getting progressively slower while I was using AVG - when I switched to Avira; it became unuseable within a week.

dansabrservices@yahoo.com: Jul 26 03:16PM -0700 My system with W10 would freeze every other day or so. Once I removed Avira, it has not frozen. I am now using AVG with no issues. I'm not sure if Avira was the problem or it just exercised code that showed the problem. YMMV Dan

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jul 27 09:18AM +1000 On 27/07/2016 7:22 AM, Ian Field wrote: > now......................................   > It had been getting progressively slower while I was using AVG - when I > switched to Avira; it became unuseable within a week.   **Last time my desktop started being flaky, I ignored it. Naturally, the HDD was on it's last legs and I lost everything. I've since re-jigged the system with the OS on the SSD and everything else is on one of those premium HDDs.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

isw <isw@witzend.com>: Jul 26 08:24PM -0700 In article <3wQlz.924111$CF.533121@fx41.am4>, > > Win7, but I can get used to it.   > So far - I'm thinking bad caps in the PSU or a virus got in when I burned > the install disk .   If the caps are an issue, why wouldn't it have affected the Linux install too?   Isaac

Adrian Caspersz <email@here.invalid>: Jul 27 08:48AM +0100 On 26/07/16 21:54, Ian Field wrote:   > A clean ground up install isn't much better...................   > When I tried to go back to AVG, the installation failed, so it looks > like I'm stuck with Avira.   Windows is like that. The alternatives aren't.   Do you want to get on with work or play games?   -- Adrian C

jurb6006@gmail.com: Jul 27 01:25AM -0700 >"If the caps are an issue, why wouldn't it have affected the Linux >install too? "   Hmm, years ago I had a Windows OS go bad. I stuck a Linux live disk in it and as it was booting I noticed it said "SOMETHING WICKED HAPPENED". But it did run after that. I am pretty sure it was bad caps.   The REAL problem comes when the bad caps cause the BIOS to get corrupted. Seen that a few times.

Wayne Chirnside <wc@faux.com>: Jul 27 12:14PM On Wed, 27 Jul 2016 08:48:05 +0100, Adrian Caspersz wrote:   >> like I'm stuck with Avira.   > Windows is like that. The alternatives aren't.   > Do you want to get on with work or play games?   I started with Windows 3.1 -DOS 5 and played around with Slackware, Knoppix then moved to a matured Mint.   I do not play games.   I do not miss the everyday hassle of keeping up with virus, Trojans and maleware.   Looked at Win 95 and 98 and saw nothing but the same and more intrusive EULA agreements.   I see the handwriting on the wall with MicroSlop going down in flames shortly as they themselves move to Linux calling it Azure but they still seek to own the consumer.   I cannot think of one single complaint of any of the GNU/Linux I used and there have been many yet none so far has let me down nor been the endless hassle MicroSlop was.   My very last encounter with Windows dual booting Linux left me infected with a boot sector virus rendering one of the two hard drives useless, care to guess what OS was on that one?   Unfortunately I'd lacked a jumper when I put that drive in so I'd soldered it, so in the trash bin it went more hassle than it was worth. It was a rather small drive so not a big deal.   Windows has not infected any machine I've owned in the last eighteen years, oddly enough dating to the last time I had issues with any of my systems.   Had Windows Ultimate on a used purchased drive, looked at it, dd if=/dev/ zero of=/dev/sda clear it right up. YMMV but I'd be skeptical.

Aardvarks <aardvarks@a.b.c.com>: Jul 26 09:32PM On Tue, 26 Jul 2016 09:05:17 -0700, Jeff Liebermann wrote: > To many financially marginal users, $1200/year is well worth the > effort and would subsidize a fairly substantial collection of > electronic burglar and reverse engineering tools.   This is a good point to annualize costs. Saving $1,200 a year for ten years is a serious tool cache! > spend my evenings in front of a computah, merrily hacking my way into > as many systems as possible. This is hardly that case, but it does > improve my otherwise lackluster and boring image.   That makes sense. Over the years, on a.i.w, you have joked that you could break in to many home broadband routers, simply because people don't secure them properly. > with Brett. No clue on the rest of the company. Several friends and > customers use their mesh wireless service. I don't hear any > complaints, so I presume it mostly works.   Good for you that you can communicate well with Brett. I guess he doesn't insult you as much as he insults less knowledgeable people. :)   Dave is just as cocky in sales. Contrast that with how Loren deals with the hoi polloi who are his customers, and it shows that these small WISP outfits have entirely different personalities when you deal with them.   The Comcast & satellite customers don't get that "personal" connection with the proprietors! :)   > Incidentally, mountain tops tend to have fiber backhauls because > that's all the telcos will provide these days. Copper is so 20th > century and so unreliable.   The mountain top I'm using *does* have a fiber-optic backhaul, so, as you noted, it's the "airtime" that limits my bandwidth (plus any throttling done by the AP operator).   > renew my drivers license and needed a suitable disguise. I shaved off > the beard but kept the mustache after the license arrived. The common > description was "motorcycle thug", not beatnik.   I bleached and sandpapered my fingerprint when I went for a license. Heh heh ... it was the wrong thumb! I was sore for a week!   > prices was military surplus. I think I had about 20 identical shirts. > I still do much the same thing today, but no more military surplus > clothes.   I buy at the military surplus stores all the time. That's where I get my boots, for example. And all my rope for climbing on the mountain. I don't think I have shirts though. I do love their parachute line which I use for lots of things except shoelaces! [Parachute line sucks at long hiking boot laces - you have to rub Elmers glue on the slippery line just to get some friction from the dried residue - ask me how I know.] > flight time, it will retry BEFORE the ACK is received. Many outdoor > radios have a "long distance" check box in the settings to increase > the timeout. Few home wireless routers have this feature.   I use the Rockets mostly nowadays, where AirOS has some pretty good diagnostics (I love the noise interference waterfall display information!)   > Ignoring the legal limit, cranking up the power output to unreasonable > levels usually causes the output stage to go non-linear.   I keep to the limit. I'm pretty much *at* the legal limit though, since my AP is something along the lines of 10 miles away (or so).   > the narrowest beamwidth dish antenna at your end, will pickup hundreds > of other wi-fi devices along the line of sight. Starbucks signal will > be buried under the interference.   I agree, even at 5GHz, noise is *everywhere*, so, I need a good dozen decibels above the noise to connect.   It would be *fun* to actually connect to a downtown library or coffeeshop from ten miles away; but, it's just not pragmatic unless I'm within a mile or two.   > outdoor client bridge radios, which are not what one would expect to > see at Starbucks. I know one local hot spot that routinely has > between one and three Ubiquiti radios connected.   Ah, that's what I thought. I would guess that a mile or two LOS is no problem. But ten miles is too far, at least for me.   > Gone to replace the LNBF on a C band dish for the 4th(?) time. It's > not tower work but still slightly dangerous.   Good luck. I bought an orange OSHA-compliant safety harness from a military surplus store if you ever want it. I never used it! You can have it. It has a big aluminum D ring sewn to the middle of the harness for safety tethering.

"Ian Field" <gangprobing.alien@ntlworld.com>: Jul 26 08:48PM +0100 "frank" <frank@invalid.net> wrote in message news:nn75r7$s1m$1@usenet.itgate.net... > electrolitics > will need to be replaced. > Frank   My experience with a colour bar generator was a cheap kit built job - the modulator was very cheap & nasty and fixed frequency.   My solution was to graft in the modulator from a scrap VCR. Most have a preset screw to move the channel - but its not designed for frequent adjustment.

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