- Oldtimer question (valves/tubes) - 20 Updates
- Water pressure pump pressure switch doesn't turn on automatically - 3 Updates
- 16 X 64 SCROLLING LED MATRIX - 2 Updates
| Look165 <look165@numericable.fr>: May 12 07:28PM +0200 ECC81 is the same. Cursitor Doom a écrit le 12/05/2019 à 13:04 : |
| Cursitor Doom <curd@notformail.com>: May 12 05:43PM On Sun, 12 May 2019 19:28:17 +0200, Look165 wrote: > ECC81 is the same. Yes, and fortunately I did have some spare new ones to try (on the suggestion of a pal of mine who I would have ignored were it not for the fact that he's 20 years my senior and has a doctorate in electronics). It didn't fix the problem - unlike him I didn't expect it to - but did tend to suggest that the issue was one of poor biasing (for whatever reason) as I'd expected. Sadly the thing has passed its prime by many years. It's not worth continuing with when you discover the many and various pot cores have nearly all been shattered by some dimwit who didn't know what he was doing. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Fox's Mercantile <jdangus@att.net>: May 12 12:49PM -0500 >> The grid/Cathode bias does change with range selection; I just measured >> it. There doesn't seem anything obviously amiss with the readings: > If you've eliminated other faults as possible then time to adjust the bias on the iffy range. There is NO adjusting the bias. It's NOT adjustable. The difference in readings is based on the difference in output for each range. It's entirely likely it was like that new from the factory. -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| Cursitor Doom <curd@notformail.com>: May 12 06:29PM On Sun, 12 May 2019 12:49:21 -0500, Fox's Mercantile wrote: > There is NO adjusting the bias. It's NOT adjustable. > The difference in readings is based on the difference in output for each > range. It's entirely likely it was like that new from the factory. Whist it's true there are no trim pots involved, the fixed resistor values will have changed over the last 65 years, which is quite possibly responsible for the fault. They would need to be hooked out individually and replaced, but it's not worth it. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Ralph Mowery <rmowery28146@earthlink.net>: May 12 04:54PM -0400 In article <-LqdnbRNIbQ8wUXBnZ2dnUU7-bPNnZ2d@giganews.com>, jdangus@att.net says... > The difference in readings is based on the difference in output for > each range. It's entirely likely it was like that new from the > factory. Most likely the difference in the Q of the circuits and maybe the gain of the tube at different frequencies. That would change the power of the osicllator and voltages. One thing I would look at would be all the reisitors in the generator. Those old carbon ones often change value after a number of years, most seem to go up in value. |
| Ralph Mowery <rmowery28146@earthlink.net>: May 12 04:57PM -0400 In article <qb9m0d$gun$7@dont-email.me>, curd@notformail.com says... > continuing with when you discover the many and various pot cores have > nearly all been shattered by some dimwit who didn't know what he was > doing. In the past some coil problems have been caused by the change in the cores. Not due to being shattered but just that the material ages. |
| Mike Coon <gravity@mjcoon.plus.com>: May 12 10:00PM +0100 In article <qb9hfa$gun$3@dont-email.me>, curd@notformail.com says... > That valve tester of yours was probably an AVO. I've got a couple of > those in my collection. Highly unlikely. I still have Dad's "Universal Avometer Model 7", so if the valve tester was from the same stable I would have linked the two. Unfortunately I can't find any record of my offer to Bletchley, to a chap who IIRC has since died. Mike. |
| Cursitor Doom <curd@notformail.com>: May 12 09:53PM On Sun, 12 May 2019 22:00:16 +0100, Mike Coon wrote: > the valve tester was from the same stable I would have linked the two. > Unfortunately I can't find any record of my offer to Bletchley, to a > chap who IIRC has since died. I think you'll find AVO took over Taylor in the late 1950s so it's all just about dates of manufacture. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| tabbypurr@gmail.com: May 12 06:12PM -0700 On Sunday, 12 May 2019 19:29:45 UTC+1, Cursitor Doom wrote: > values will have changed over the last 65 years, which is quite possibly > responsible for the fault. They would need to be hooked out individually > and replaced, but it's not worth it. One needs replacing. Sounds like a trivial job. Send it to me if you want. NT |
| Mike Coon <gravity@mjcoon.plus.com>: May 13 11:35AM +0100 In article <qba4km$gun$9@dont-email.me>, curd@notformail.com says... > > chap who IIRC has since died. > I think you'll find AVO took over Taylor in the late 1950s so it's all > just about dates of manufacture. Oh, thanks, I might look that up. But the valve tester would certainly be older than that. It did have a lacquered wooden case, after all! Mike. |
| Lucifer <LuciferMorningstar@bigpond.com>: May 13 08:46PM +1000 On Sun, 12 May 2019 11:04:06 -0000 (UTC), Cursitor Doom >range switch is switching in different combinations of coils and >capacitors, but is it likely to be also switching in different cathode- >grid DC biasing at the same time? I have a Radiosonde weather balloon transmitter which has a single valve. The valve is a 3A5 twin triode with one being the RF oscillator at 72 MHz and the other an audio oscillator which was controlled by the sensors. I did have a one valve test oscillator which was powered by a nine volt grid bias battery. |
| Lucifer <LuciferMorningstar@bigpond.com>: May 13 08:53PM +1000 On Sun, 12 May 2019 15:53:17 -0000 (UTC), Cursitor Doom >It breaks my heart to do this, but I think it's a junker. On further >inspection some screwdriver jockey's fucked around with it and since I >only paid a fiver for it, it's time to consign it to recycling. I picked up a valve paging transmitter from a rubbish tip. It was in working order, 5 watts output on 27.212 MHz, with the crystal in an oven. |
| Cursitor Doom <curd@notformail.com>: May 12 03:53PM On Sun, 12 May 2019 08:46:42 -0700, tabbypurr wrote: > If you've eliminated other faults as possible then time to adjust the > bias on the iffy range. It breaks my heart to do this, but I think it's a junker. On further inspection some screwdriver jockey's fucked around with it and since I only paid a fiver for it, it's time to consign it to recycling. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Mike Coon <gravity@mjcoon.plus.com>: May 12 05:02PM +0100 In article <qb9fhd$gun$2@dont-email.me>, curd@notformail.com says... > It breaks my heart to do this, but I think it's a junker. On further > inspection some screwdriver jockey's fucked around with it and since I > only paid a fiver for it, it's time to consign it to recycling. The computer museum at Bletchley Park has (or had) a valve re-cycling exchange. I bequeathed (or dumped) my father's collection of valves and his (Taylor?) big wooden-cased valve tester to them and they made appropriate gratitude noises... Mike. |
| Cursitor Doom <curd@notformail.com>: May 12 04:26PM On Sun, 12 May 2019 17:02:11 +0100, Mike Coon wrote: > exchange. I bequeathed (or dumped) my father's collection of valves and > his (Taylor?) big wooden-cased valve tester to them and they made > appropriate gratitude noises... Oh, I save the tubes alright; I'm not that much of a philistine. That valve tester of yours was probably an AVO. I've got a couple of those in my collection. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Cursitor Doom <curd@notformail.com>: May 13 11:23AM On Mon, 13 May 2019 20:53:55 +1000, Lucifer wrote: > I picked up a valve paging transmitter from a rubbish tip. > It was in working order, 5 watts output on 27.212 MHz, with the crystal > in an oven. Nice find. It's amazing what gets thrown out! I dream of owning an apartment overlooking a vast garbage tip so I can spot anything potentially valuable being dumped. ;-) -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Cursitor Doom <curd@notformail.com>: May 13 11:26AM On Sun, 12 May 2019 18:12:10 -0700, tabbypurr wrote: > One needs replacing. Sounds like a trivial job. Send it to me if you > want. Thanks for the offer, Tabs, but it's too far gone in other respects I'm sorry to say. Trust me, I hate throwing anything away so it really has to be terminal case for me to even consider junking it. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Cursitor Doom <curd@notformail.com>: May 13 11:31AM On Mon, 13 May 2019 20:46:03 +1000, Lucifer wrote: > I did have a one valve test oscillator which was powered by a nine volt > grid bias battery. Tust the grid alone was battery powered? Seems a bit of a strange idea. I mean, it's entirely feasible, but if you have to generate higher voltages for the anode from the mains.... -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition. |
| Lucifer <LuciferMorningstar@bigpond.com>: May 13 09:46PM +1000 On Mon, 13 May 2019 11:31:05 -0000 (UTC), Cursitor Doom >Tust the grid alone was battery powered? Seems a bit of a strange idea. I >mean, it's entirely feasible, but if you have to generate higher voltages >for the anode from the mains.... The nine volts was the anode voltage! I had a hybrid car radio with 4 valves and 2 transistors. The valves used the 12 volts for the anode voltage. Valves don't need high voltage on the anode for low power applications. |
| Lucifer <LuciferMorningstar@bigpond.com>: May 13 09:52PM +1000 On Mon, 13 May 2019 11:23:51 -0000 (UTC), Cursitor Doom >Nice find. It's amazing what gets thrown out! I dream of owning an >apartment overlooking a vast garbage tip so I can spot anything >potentially valuable being dumped. ;-) I have found so many amazing things at tips. A bag of stained glass hobby bits and pieces. Photo copiers I spent hours dismantling. Auctions are a good cheap source of what many people call junk. |
| Adrian Caspersz <email@here.invalid>: May 12 10:59PM +0100 On 12/05/2019 16:07, Prouvost wrote: > System overview videos > (1) [https://youtu.be/X4TZoFIsE2w] > (2) [https://youtu.be/CQayY5FTNKk] Does his style of posting look familiar ... -- Adrian C |
| Rheilly Phoull <rheilly@bigslong.com>: May 13 09:01AM +0800 The proposed action seems good but save time and check for the blockage first, the pressure switches dont change setting much, the one thing to get on top of is to regularly check and adjust the pressure in the tank (The static air pressure) that does gradually change. On 12/05/2019 11:07 pm, Prouvost wrote: |
| "pfjw@aol.com" <peterwieck33@gmail.com>: May 13 04:13AM -0700 On Sunday, May 12, 2019 at 5:59:55 PM UTC-4, Adrian Caspersz wrote: > Does his style of posting look familiar ... Style is familiar, yes. And the essential idiocy has not gotten any better with time. Peter Wieck Melrose Park, PA |
| fynnashba@gmail.com: May 12 02:11PM -0700 I have an arduino mega 2560 and wants to use it to drive a 16x64 LED array but the outputs are not enough, Is there any way i can achieve this? Thank you. |
| Adrian Caspersz <email@here.invalid>: May 12 10:52PM +0100 > I have an arduino mega 2560 and wants to use it to drive a 16x64 LED array but the outputs are not enough, Is there any way i can achieve this? Thank you. google "addressable latch" e.g https://www.tigoe.com/pcomp/code/arduinowiring/486/ -- Adrian C |
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