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Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Dec 02 02:59PM -0500 On 12/2/18 2:26 AM, Fox's Mercantile wrote:   > A DMM won't read correctly. No enough voltage compliance on the current > source to read ohms correctly. > Just replace it with a 1N4007 diode and about 100 ohms series resistor.   And watch out for confetti. ;)   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Phil Allison <pallison49@gmail.com>: Dec 02 10:06PM -0800 Fox's Mercantile wrote:   > > during this test.   > A DMM won't read correctly. No enough voltage compliance on the current > source to read ohms correctly.     ** Most DMMs have separate ohms and diode tests ranges, the ohms ranges are for " in circuit" resistor testing and will not make a good Silicon or Selenium diode conduct.   > Just replace it with a 1N4007 diode and about 100 ohms series resistor.   ** Really ? Only the wimpiest rectifier has 100 ohms series resistance, like a Germanium detector diode.   The OP's Selenium rectifier powers an AM / FM radio,( minus less the tube filaments ) so ought to be good to half an amp - so maybe try 22 ohms @ 5watt.     .... Phil

tabbypurr@gmail.com: Dec 02 10:47PM -0800 On Sunday, 2 December 2018 13:27:47 UTC, Adrian Caspersz wrote: > On 02/12/2018 13:03, tabbypurr wrote:   > > I replaced some parts on my 1934 set, but you'd never know by looking inside. The new parts are inside the old, which are repacked exactly as original. With selenium you could possible hide the diode somewhere not noticeable, keeping the selenium in place.   > To maintain the authentic smell?   obviously there won't be any smell from a selenium rectifier that isn't seeing power.     NT

tabbypurr@gmail.com: Dec 02 10:54PM -0800 On Sunday, 2 December 2018 16:15:37 UTC, Cursitor Doom wrote: > > noticeable, keeping the selenium in place.   > Yes, I'm aware of this practice, but for some super-fussy types, it's > still not good enough.   I like my kit to work. If some folk want theirs dead, I guess that's their call. There was no chance of it working without repair. FWIW having old kit that doesn't work is missing much of the experience.   With the selenium rectifier, you could still use it if it still works, but its toxicity is a problem that needs addressing somehow. That gets difficult, though not impossible.     NT

MOP CAP <email@domain.com>: Dec 03 07:25AM -0800 Seleniums have a shelf life. By their very nature the go bad over time. Thus any selenium out there is bad as they have not [at least in the US} been made in a shelf life time. CP

"pfjw@aol.com" <peterwieck33@gmail.com>: Dec 03 04:08AM -0800 http://www.nucow.com/alldial.htm Here   But, you will find that most of them are quite intuitive. No radio manufacturer wanted this to be complicated - complication takes time.     Peter Wieck Melrose Park, PA

John-Del <ohger1s@gmail.com>: Dec 03 05:12AM -0800 On Sunday, December 2, 2018 at 3:08:08 AM UTC-5, John Robertson wrote: > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."     Back in the old days, we'd always use the OEM switch/control assy when the part store had them, but there were so many different types that often the OEMs weren't available, so the counter guy would go through the Centralab book, and come to the counter with a collection of parts and we'd assemble the control right there. The only two issues were that we'd often have to cut the shaft down a bit to make the length correct and the universal snap in shaft had a bit of tactile free play that the OEM didn't, but otherwise it was a fast and long term solution as the Centralab stuff was well made. BTW, was CTS a different company or the same as Centralab?

The Real Bev <bashley101@gmail.com>: Dec 02 07:43PM -0800 Everything worked, but the screen was unresponsive. For once, I googled before asking. The problem is crud between the screen and the frame. Carefully drag the corner of a piece of ordinary paper under the edge all the way around. Yeah, I was suspicious too, but it worked!   -- Cheers, Bev Some people are like Slinkies... Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.

etpm@whidbey.com: Dec 02 12:45PM -0800 On Sat, 1 Dec 2018 17:36:04 -0600, Fox's Mercantile <jdangus@att.net> wrote:   >> xmfr at PartsExpress.   >The only thing that matters is the amp rating of the secondary. >Equal or greater than the load. Thanks Jeff. Your answer means I can use the lower amperage xmfr I also looked at. It has a 3 amp rated secondary. Eric

etpm@whidbey.com: Dec 02 12:46PM -0800 On Sat, 1 Dec 2018 20:45:41 -0500, Tom Biasi <tombiasi@optonline.net> wrote:   >> Thanks, >> Eric   >If all the 110 volts does is make DC why can't you just clamp the DC? It's a tube amp. Seems easier to just feed it the correct voltage. Eric

etpm@whidbey.com: Dec 02 12:47PM -0800 On Sat, 1 Dec 2018 19:27:11 -0800 (PST), John-Del <ohger1s@gmail.com> wrote:     >> If all the 110 volts does is make DC why can't you just clamp the DC?   >What if it's a tube amp?   >It's still easier to add a buck transformer than add a regulator circuit (not a great idea to "clamp" the DC). You got it John. I should have mentioned that it was a tube amp, I gues. Eric

etpm@whidbey.com: Dec 02 12:49PM -0800 On Sat, 1 Dec 2018 23:38:23 -0500, Ralph Mowery   >> I didn't think a tube amp would be so fussy about the supply voltage.   >They are probably more fussy about the supply voltages. The filiments >of the tubes burn out faster if the voltage is too high. Yeah, that's apparently correct, from everything I have read and watched about tubes. Eric

Fox's Mercantile <jdangus@att.net>: Dec 02 05:42PM -0600 > Thanks Jeff. Your answer means I can use the lower amperage xmfr I > also looked at. It has a 3 amp rated secondary. > Eric   Obviously, what I should have included is adding a margin of safety. A 3 amp secondary used to buck a 1.5 amp load is just fine.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Tom Biasi <tombiasi@optonline.net>: Dec 02 07:38PM -0500 >> If all the 110 volts does is make DC why can't you just clamp the DC? > It's a tube amp. Seems easier to just feed it the correct voltage. > Eric   I'm just curious as to what product has that spec. 110 VAC on an old amplifier means line voltage in North America. The 5% is odd to me.

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