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Dennis:

I know you are not looking for a PDF but I have a scan of a 7104 manual dated "First Printing NOV 1978, Revised FEB 1989". In the "MANUAL CHANGE INFORMATION" at the rear of the manual the latest change is dated 4/20/88, "Change Reference C110/0588 Rev 2".
It matches up very nicely with the two 7104 late S/Ns (B074xxx and B084xxx) that I have. I am not sure where I got this scan from but I don't see the usual "watermarks" from Artekmanuals so I would guess I didn't buy it from Dave.

Just to let you know about the latest 7104 OP/SM that I have found out there on the web. Just FYI for everyone
Bill

A word of caution about these extender kits. I have seen these postings on e-bay from time to time and noticed that these kits use a simple circuit board whose edges are either sheared or more likely, routed with a tungsten carbide cutter. Mating the edge that plugs into the mainframe connector will likely damage it on the first insertion. The edge card connectors in the mainframe are plated with hard gold, to a thickness of 100 or 250 micro inches, depending on the vendor. This is a relatively thin plating for a connector that sees a lot of cycles. To be honest, the mainframe connectors used by Tek were not a good choice for this application. They were intended for use in semi-permanent applications, where the only cycling would be board replacement during servicing – not a plug-in where they may see hundreds of cycles in normal life. The vendor’s data sheet for the connectors stated that there design life is only 25 mating cycles. Note that exceeding this cycle count does not necessarily mean the connector would fail, but rather the specifications for contact resistance would not necessarily be met after 25 cycles.

Tek mitigated this short life by treating the male mating fingers on the edge of the plug in. If you look closely at any TM500/5000 plug-in, 5000 series scope plug-in and the Tek made extender cables, you will note several things. First, the fingers themselves are gold plated with 100 micro inches of hard gold over a nickel plate. Copper and nickel are much harder that hard gold and will deform it when mated. More important, the mating edge is treated in two manners. First, it is chamfered to a 45 degree angle with a carbide router bit by the board fabricator. This is essential to prevent the exposed glass fibers from the board edge from scraping the gold off the connector. Again, a single mating with an epoxy glass circuit board into one of these connectors can remove considerable amount of the gold plating from the connector, rendering if venerable to corrosion in high humidity environments.
While the chamfering reduces the likelihood of glass scraping the connector when mating, the step where the circuit board foil trace mates would still scrape when it mates. Tek prevented this by “rolling” the chamfered edge of the circuit board. The finished board after plating is ran through a pair of conical rollers that actually smashes the circuit board which reduces the thickness of the plated board fingers, allowing them to partially engage into the connector before beginning to deflect the spring function of the contacts. Thus, there is no edge scraping on the connector during the mating process. The board edge engages before it begins to force the contacts open.

Users who buy these extender kits can do some of these steps to improve them to prevent connector damage. Using a file, it is possible to put a chamfer on the mating edge. A short length of steel rod can be used as a roller to manually squeeze the connector edge. The only thing the user cannot do easily is add the gold plating, but the contribution of plating is minor compared to the problems of mating a rough exposed epoxy glass board into the mainframe connector.

On Mar 11, 2019, at 11:53, Bill <wpgold3637@...> wrote:

Dennis:

I know you are not looking for a PDF but I have a scan of a 7104 manual dated "First Printing NOV 1978, Revised FEB 1989". In the "MANUAL CHANGE INFORMATION" at the rear of the manual the latest change is dated 4/20/88, "Change Reference C110/0588 Rev 2".
It matches up very nicely with the two 7104 late S/Ns (B074xxx and B084xxx) that I have. I am not sure where I got this scan from but I don't see the usual "watermarks" from Artekmanuals so I would guess I didn't buy it from Dave.

Just to let you know about the latest 7104 OP/SM that I have found out there on the web. Just FYI for everyone
Bill

Chuck: Very frustrating,

Mine are perfect at the center and only have the bends in upper right of display.

RE 87>100 V test, my gut feeling is that if the GEOM pot is far from center the issue is elsewhere, perhaps a bad CRT?

Can you post a photo of the problem?

I found it useful to try both vertical lines and horizontal lines separately to see the GEOM effects.

The GEOM pot transitions typical pincushion>flat>barrel dist. uniformly over the screen.

The bending seems an aberration.

Good luck!

Jon

Hello again:

1/ Magnetic shield, degauss: I found an ancient Akai bulk degausser, and used a variac. With 40 VAC line, slow approach to the crt face gives the characteristic waving traces, beating at line freq. About 6" with the waving ~ 1 div, and gradual removal, I saw no permanent change in any part of the display. So geometry issue is not magnetization or the CRT Mu shield.

2/ I used a TEK 2901 marker gen, at 50 uS PRF, and with marker amp for 25 V pulses. The vertical is set to show just the middle of the pulse to avoid the fall time slope.

3/ Result: 2467: Perfect
2465B: Perfect
2467B#2 similar to 2467B#1 in the photos, but not a bad:

vertical lines almost perfect, same horizontal: fine in lower half, upper 2 or 3 div have just perceptible upward bend on right side of display.

The SNs of the two 2467B:

B0508xx, B0502xx so very close.

NOTE: DO NOT adjust any CRT trimpots unless necessary, since they can change the deflection factors and thus require a complete CAL 01, CAL 02, Hor and Vert!

Enjoy!

Jon

RS wouldn't allow me to enter any country except the UK when I tried to buy a couple.

Digikey says they'll have them in late May. I'm sure ST only makes a small run, probably just once a year, because of the shelf life issue.

I asked a NA eBay seller about the origin and date code of their stock. Came from a defunct distributor, but have a 2002 date code.

Unfortunately, with Farnell and their many names and websites, there is no telling where their stock is. If shipment is by sea from the UK it might still take until June :-(

so it looks as if I'm just going to have to wait.