744a
Looking for feet for my new scope, does anyone have suggestion or can print them?
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mystic96
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#192475
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Re: Thinking on CRT restorations for double peaking tubes.
Zen,
I think the consensus was (last time this was discussed, about a year ago) that double peaking is the result of irreversible damage to the cathode coating. I'm not saying that the consensus is
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Jeff Dutky
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#192474
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Thinking on CRT restorations for double peaking tubes.
I have a few tubes in the back room that are double peaking now and I was reading a few things on line, which is dangerous I know. but it got me thinking would 2 SMU units be able to do a tube
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Zentronics42@...
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#192473
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Re: 453 service manual
Have you taken a look at what's available at tekwiki?
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
http://www-smirc.stanford.edu
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Tom Lee
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#192472
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
I wonder if any lawsuits over the similarity in names.? MOSTEK? MOS TEK? verses MOS Technology.? I remember Commodore had very fast turnaround when upgrading design on their color chip because
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Carl Hallberg
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#192471
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453 service manual
Hi all,i am trying to find a manual to repair my 453,its a later fet model not the A verson,can anyone point me where to download it from?,tia.
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Paul M3VUV
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#192470
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Re: Peltola Connectors
That center pin was difficult for the final assembly people too. Later in the 7000 series life, manufacturing engineers identified as many Peltola GND sockets as possible that could be rotated for
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Clark Foley
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#192469
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
Commodore used MOS Technology chips, since they owned the company.
[email protected]> wrote:
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Michael A. Terrell
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#192468
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
Sorry about an error in the flat pack chip I'm looking for.? I wrote TA7761P and should be TA7761F.? Off topic.
Carl Hallberg (W9CJH)
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Carl Hallberg
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#192467
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
The Motorola ROMs may be better than the Mostek mask ROMs but they are not immune to ROM rot. The Motorola ROMs in my 7854 went bad.
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Stephen Bell
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#192466
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
On my mini-board I have brought out the three pins required for programming the onboard EEPROM into a header provision so you can directly program the EEPROM without any high voltage programmers.
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Ram
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#192465
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
I have a whole tube of mcm68764L eproms.? If these can replace the proms, I will mail 5 to someone who can and wants to program them.? I cannot find data sheet on Google, so don't know specs.? One
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Carl Hallberg
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#192464
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
The extra hardware for patching consisted of an FPLA (Field-Programmable Logic Array) and a PROM. The FPLA monitored the address bus, and on certain ranges it rerouted Chip Select from the mask roms
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Dave Wise
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#192463
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Re: 475 Electrolytic Cap Replacement
I used this to find capacitors for my 475. Those that you have listed are already obsolete but the rule you posted helped me find what I was looking for. I will update what I used once I have finished
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Terry
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#192462
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Peltola Connectors
If anyone is troubleshooting 7000 series circuit boards, be especially careful when re-inserting the Peltola connector wire. It is very easy to have the protruding wire miss the receiving hole and
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Gary Robert Bosworth
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#192461
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Re: tek 453 external trigger input
Hello,
The upper right bnc only affects the delayed signal. Why not try the one for the A time base, at the lower right?
A simple 1-volt p-p signal works fine for a trigger level. Also, try using
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Mike Merigliano
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#192460
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
Hi RAM,
I realize that I didn't even mention your solution/device, which I think is very elegant. Programming the device may be a complication for some though. Can a simple device like the popular
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Raymond Domp Frank
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#192459
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tek 453 external trigger input
Hi all,ive just got around to looking at my 453 fet model,its lost its triggering,i want to use the external trigger input on the top r/h bnc,just for diagnosis,what signal is needed,ie level
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Paul M3VUV
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#192458
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Re: Tek 453 resistor specs -- Horiz amp
The diode addition is around Q664, half of the slope comparator pair of transistors. (B-time base) There is also an extra resistor. The soldering looks very neat, as if it was done at the factory, but
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Mike Merigliano
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#192457
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Re: (7854) A Drop-In Replacement for the MCM68766 EPROM
Brian - The schematic is quite simple and I'd be happy to share it in reply to a PM.
Raymond - thanks for correcting me on the ROM rot in mask ROMs.
Best - Ram
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Ram
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#192456
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