31 Jan
2012
31 Jan
'12
3:48 p.m.
On 01/31/2012 03:53 PM, Tony Duell wrote:
Actually a storage version of the 555 would be fun. The only storage
'scope I know of in this series (and I don't have one) is the 549, which
is a storage 545 IIRC.
I have a 549. It's a beautiful instrument, as should be expected.
The brightness of the stored trace isn't as good as it should be, but
I've not yet gone into troubleshooting it.
Eek.... One of the few times a vlave tester would have been reliable in
finding the fault (see another thread). On the other hand, it's not hard
to check the reisstnace between pins 3 and 4 with an ohmmeter.
...which is exactly what I did.
It's a pity there never was a double-beam
'scope in the 580 seires. Now
that would be serious fun.
Oooooh yes. With storage, too. :) Incidentally, if you get a chance, l ook at hte 564
'scope manual, in
particualr the storage system scheamtic. The cleaning lady mopping up the
water put there by the flood gun is a classic...
Yes. :-)
I thought EB91s (6AL5s, whatever) went on for ever...
Nope, not this one. It had an open filament. "Gee, why is this tube
cold?" :-) Years ago over here there was a simple battery + bulb
continuity tester
sold with varios valve sockets on it, The tester was wired to the heater
pins of the sockets (pins 4 and 5 of the B9A, pins 3 and 4 of a B7G, and
a segond B7G with 1 and 7 wires 'for battery valves only' and so on. It's
actualyl quite useful for weeding out totally dead valves before you use
the AVO Mk 4 or Tekky 570 ;-)
Or before you mortgage your house to buy a 570!
-Dave
--
Dave McGuire
New Kensington, PA