(27-07-2015, 03:19 PM)AlanBeckett Wrote: I suspect you're right Jeffrey. According to the Data Sheets there's little point using the 'A' Version unless the rest have similar Characteristics.
Alan
Not necessarily Alan. Depending on the actual design of the PSU, one valve which doesn't conduct until well after the others could hold a rail down until the others had stabilised. This is used in several pre-war TVs where the EHT rectifier has a very high thermal inertia heater so that the scans are up before EHT is applied to the CRT. Looking at your PSU, the main +225V rail is a straight forward series regulated jobbie so I thinks you're right in this case. However, the circuit does state 6U8, not 6U8A so possibly the valve that was in the equipment was one that was to hand last time the kit was repaired!
