1987 Power transformer How many 12ax7 can it use?

[RockinRocket]

The particular power transformer is a Merrin 1202-118 1987 model. I may get a dual volt transformer for my 1987 and was wondering for a possible project if a 1202-118 Marshall or Merrin transformer can handle 2x El34s and 5 12ax7 no problems?

[Bob S]

The extra ht current required is very little - less than 12mA.
Figure on an extra 0.6A for filaments. More of a consideration.

[RockinRocket]

Ive seen quite a few 1987s with a extra tube for a loop or gain stage. With rising wall voltages the filaments should be fine me thinks for 2 more 12ax7s??

[Littlewyan]

Going by the Magnetic Component Power Transformers for Marshalls it should be fine. They handle 5A on the 6.3VAC winding.

Rising wall voltages have very little to do with what the PT can handle. It does effect it but its very minimal. So can be forgotten about to be honest.

Email Chris Merrin, he'll happily tell you what it can handle if you want to be sure. Hes a nice guy.

[Firestorm]

Pretty sure Chris overbuilt. Yes, he is a great guy. Worked with Ken IIRC.