Mark III 105 voltages

[Thaymz]

Hi all

Potentially daft question. A little while ago I was fortunate to find an 85 no stripe with the 105 PT. I was wondering if the 105 in the III has the same plate voltages as it does in the IIC+, and therefore need some 415/416s to withstand the voltages (ie 483v+). Or is there something else in the circuit that would tame this?

I currently have 440s in there and 1) don't want to cook them unnecessarily as they aren't getting any cheaper or 2) don't want to use some of my 415/416s if there is no benefit in doing so.

 

[Joey1970]

I would burn through those Chinese tubes like they were candy. The USA made ones will last a lifetime.

 

[Boogiebabies]

My reference to the 105 at 483V DC is under load.
It puts out 510V or so. The STR-440 is fine. If you have the
Resources, an STR-415 and STR-416 would last for many years
As the current manufacture tubes will go a few years under
Normal use.

 

[GJgo]

If you don't want to spring for high dollar, old, questionable 415s, there are modern alternatives for the high PV amps.
- JJ / Mesa STR445
- TAD 6L6GC-STR
- The Tube Store Preferred Series 6L6GC-STR (essentially the same as the TAD)