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bob prohaska <bp@www.zefox.net>: Aug 13 02:08AM Does anybody recognize the DC motor controller in the photograph at http://www.zefox.net/~bob/lathe/motorcontrol ?   There are a few other photos in the same directory showing detail views of a few items in the enclosure. There are no names, part numbers or any other identifying marks that I can find on the board. The only IC visible is a National 741NC, I think the date code reads February, '81. The Reliance Electric output device is a 701819-X, described as a rectifier. With six leads it might be a thyristor of some sort, but web searches haven't confirmed it.   I'm looking for information becasue I'd like to change the wiring harness to relocate the controller for better space utilization. Before I mess with it I'd like very much to know how it works, so if/when I make a mistake there's a chance of fixing it.   At the same time it would be helpful to know what it'll take to replace it, in case I can't or don't want to modify/repair it. The motor is a half horsepower shunt wound DC 1750 RPM Browning. Web searches for the various numbers on the nameplate come up mostly with firearms links, so I gather Browning is no longer in the motor business.   The application is an old South Bend lathe. Apparently somebody wanted to wind coils, so they added a soft-starting variable speed drive and a turns counter. If I kill the DC setup I can always fall back to a traditional fixed-speed motor but the present setup is very nice and I'd like to keep it working if possible.   Thanks for reading,   bob prohaska .

MOP CAP <email@domain.com>: Aug 12 07:20PM -0700 On 2017-08-13 02:08:44 +0000, bob prohaska said:     > Thanks for reading,   > bob prohaska > .   It might help if you could move the wires that obscure the marks on the 6 leaded module not on the circuit board. Barring that what does it say?

N_Cook <diverse@tcp.co.uk>: Aug 13 07:50AM +0100 On 13/08/2017 03:08, bob prohaska wrote:   > Thanks for reading,   > bob prohaska > ..   Main board looks more 1970s than 80s with carbon Rs and canned opamps, if 80s perhaps JFET ones. The lower left white board is later with MO resistors. At least the opamps , easy to monitor DC levels and then try a compatible opamp in the socketted one.

knobbler1@gmail.com: Aug 12 12:36PM -0700 On Thursday, August 10, 2017 at 7:58:37 PM UTC+1, N_Cook wrote: > "Style" looks rather kit-form. Reminds me of the South African brand > Sabtronics around in the UK then , in the same sort of general purpose > case and simple typography and exposed bulkhead connectors   The company that made it is still going today but they have moved onto making climatic test chambers now and have no records available of their electronic test gear product range which they ceased production of 30 years ago. It is a British company and I have posted some photos of it here which might possibly remind you of something? <https://www.eevblog.com/forum/testgear/brand-name-i-never-heard-of-before/>

Madness <madness.mail@gmail.com>: Aug 12 02:32PM -0400 ***BBBBBBRRRRRRAAAAAAAPPPPPP!!!!!!***

"David Farber" <farberbear.unspam@aol.com>: Aug 12 09:08AM -0700 David Farber wrote: > find out the procedure to remove the knob in a manner that wouldn't > force or break anything. A new timer has already been purchased.   > Thanks for your reply.   When the knob is pushed in, it spins AND SO DOES THE SHAFT without any clicking noises. I think what has happened is whatever mechanism that engages the shaft to the gears inside the timer is broken. Since the mechanism's gears are not applying any locking action in the counter-clockwise direction, the knob cannot be unscrewed. This knob is not like the other knobs on the washer. It needs to be unscrewed. It cannot be directly pulled off. The only solution I can think of is to put some glue inside the back of the timer where the shaft is. Maybe it will lock the shaft into place so the knob could be unscrewed.   -- David Farber Los Osos, CA Thanks for your reply.

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