Chris, Thanks for the reply. I have made just such a mod to one of my 58503's. It was in a discussion of this mod that the idea arose that HP had built in such a command. But, no one had actual knowledge of such this hidden command. It was most probably just wishful thinking. Thanks again for your comments. 73 de Lon , K5JV
On Mon, Jun 6, 2022 at 11:33 PM Chris Hastreiter via time-nuts < [email protected]> wrote: > I'm not aware of any command to turn off the display - I haven't seen it in > the manual, but I think that it might use the same display interface as the > 53131A counter. For that unit I've added a two pole switch that allows me > to turn off the anode and filament voltages to the display when I'm not > using it. You could measure the voltages on your interface cable and see > if it matches the 53131A schematic and if so do something similar. > > Chris > > On Fri, Jun 3, 2022 at 5:47 PM K5jv via time-nuts < > [email protected]> > wrote: > > > I was recently evolved in a discussion about the HP 58503 option 001 > > display. The general idea is that there is some command to tune the > > display on or off. A few ideas were offered but no one had anything > except > > "they heard about it." I have found nothing on the subject from old HP > > literature. Comments would be appreciated. I am not talking about > turning > > the power off to the DC/DC converter. > > > > On a different subject: A couple of month back I got some strong > > criticism about suggesting that the oven in the Z3801A was a potential > > source of problems. I just got another Z3801A in for repair. Same > > symptoms as before; appears to turn on normally but after a while goes > > into holdover and stay there, same LH flat lines. Once again the > problem > > turned out to be the oven. It was unusually hot to the touch. Changing > > the oven solved the problem. Now my question. I have never opened one > of > > these oven, so have no real idea exactly what is inside. I would > suspect > > that one of the oven's thermostats is stuck in the "on" position. Since > > it is a "double oven", there could be two thermostats? If these are > > mechanical contacts, as one might expect fro the 1995 era, can they be > > cleaned or replaced? Comments from anyone who has actually seen inside > > one of these ovens would be appreciated. > > > > > > 73 de Lon, K5JV > > 281-795-1335 > > > > > > [a96323c7-47c0-46b2-8018-f039618476d5] > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe send an email to [email protected] > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe send an email to [email protected] > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe send an email to [email protected]
