P { margin-bottom: 0.21cm; }I recently was given a 7934 minusplugins as 'spares or repair' and was surprised to find that innon-storage mode everything that I have tried so far works perfectlyand the bandwidth and triggering seems fine. The trace is sharp, but a bitfaint on the fastest speeds (about 10kHz rep rate from an avalanchepulse generator) but fine with the room lights dimmed.
I have to admit to never having used astorage oscilloscope! We had the Tektronix 611 storage display unitattached to a mini-computer before raster graphics displays wereaffordable (colleagues at NASA Goddard had a colour graphics displaythat cost $250k) and later I used the Tektronix 4010 computergraphics terminals quite often so I am used to some of the artifactsthat you get with storage displays.
My question is whether my 7934 just hasan aging CRT or may need some adjustment on the voltage settingsaround the storage control. Currently the 'level' control on thetop right of the panel has its spindle broken and I cannot adjust it,a replacement is on order but will probably not arrive for a week ortwo. I don't claim to have made any exhaustive checks of the storageoptions (largely since I don't know what to expect!) but in generalterms I have a rather bright uniform background in storage mode. Some combinations of settings will darken the background but notuniformly (darker centre, bright edge) and the trace and readout arereasonably sharp against the brighter background but become blurredon the settings with better contrast. Save and erase do what youwould expect given the bright background.
So basically, if the tube is on the wayout then I will give the 7934 a wash and brush up and concentrate ongetting my 7904 100% right instead of the 99% at present. On theother hand if there is the prospect of improving the storageperformance with a bit of work then I can start reading and learningabout storage tubes and do a check on voltage levels while waitingfor the replacement pot to arrive.
Also a Merry Christmas to everyone,
Roger
