Recent content by RobS

That may explain why I was able to acquire a control panel originally used in a college in Kennesaw Georgia. I think the other one promised to me in California had originally been on a military site there. When our purchased company H200 here in the UK was scrapped at the end of the 1960s...

I think the situation in the UK was different from that in the USA because there was not such a large market here, so leasing wasn't so viable. Also British computer manufacturers had a larger share of our market. In fact I am currently arranging with our National Collections Centre access to...

As I explained in my article in RESURRECTION, the house magazine of the Computer Conservation Society here in the UK, my original reason for conceiving the project was as a way to get rid of a load of obsolete electronics stacked in my garage after my mother-in-law died and we had to move it all...

How old were you then? I recall the console on one of our later machines developing an embarrassing fault. Given what has already been written here about the console printer mechanisms I don't know why one particular print position would stop printing but it did on our console. One of the...

It may just be a coincidence. The STOP and RUN buttons would be in the bottom row because they were often used and operators got into the habit of pushing STOP at the same time as INITIALIZE, so INITIALIZE was placed next to STOP to make that easy. INITIALIZE and SYSTEM CLEAR didn't contain...

I haven't tried using the waxed nylon cord I bought yet but it is made by a European company, SES Sterling, who state that the fibres in it spread out flat to reduce the chance of it cutting into fingers or the insulation on wires as well as ensuring that knots stay tight. That implies that the...

I don't know about TTY print mechanisms but making a realistic Honeywell console keyboard wouldn't be too much of a problem. There appear to be images of one in use two minutes into the title sequence of the film Billion Dollar Brain and it looks like the mechanism is similar to the Honeywell...

My H200 panel pictured previously HERE also has nylon cable ties which are possibly the originals although there is also some lacing. The H200 cable harnesses also from the early 1970s that I acquired had waxed lacing as you say. I was surprised about those nylon ties but that supports my...

But not any more? I always have to deliberate about which aspects of my home brew machine need to be similar enough to those on the original H200 to make it an equivalent. I have been obliged to take liberties with the internal logic as a consequence of the original components and schematics...

I only just noticed this comment. On this occasion it's purely a coincidence that I'm mentioning the Honeywell 200 on a thread about the IBM 1401 but the chap who was probably the last working H200 field engineer in the world told me that the H200 machines that he kept running up until year...

I agree about the crazy price for 382 lamps but maybe this is because they still crop up elsewhere such as in plane dashboards. When our company scrapped some Honeywell equipment I also raided the engineers' workroom and acquired boxes with 100 382 and 387 lamps in them, so hopefully they'll...

BBtheEE , While testing the panel using a level DC PSU with all lights lit by INITIALIZE it did consume something over 6 Amps as you suspect. I can't directly measure the fluctuating PSU voltage that I am now using, so monitor it with my oscilloscope and the constant voltage transformer does...

I did a rough calculation of the RMS value of the voltage supplied by my pulsating waveform and it came out as 14.6 volts RMS, so it's right on target. Also it varies very little regardless of the load, which is good.

I have now tried connecting the control panel to the CVT-plus-diodes based PSU and during this trial panel lights did both come on and go off, so the intermittent supply waveform shown on my previous post is shutting off the SCRs as expected. A supply similar to this must have been used in the...

The rectified waveform from my CVT looks much better under a 40 watt dummy load and the buzzing is quieter. As the current demand from the lights in the control panel varies so widely I may have to find something else to put a more constant load on the CVT apart from the panel. However, as the...