5F6-A Choke Problem/Questions?

[tonecat]

Hello All,
I was doing some testing of various parts on my recent bassman clone. I decided to check the DC resistance of the choke and it was only 39 ohms. Does this seem a little bit low? The choke is a Mercury Magnetics 2.84 H bassman toneclone. The replacement chokes for other 6L6 Fender amps like the 125C1A are around 4 H, 90 mA and 110 ohms DCR. I have a 5 H, 100 mA 352-114 Heyboer (Drake clone) choke that reads just over 100 ohms DCR. How do you think this would work on the 5F6-A/JTM 45 circuit in place of the low reading Mercury? I have no way to test inductance and really don't know much about how to test chokes any other way. Any thought or ideas would be appreciated!! Thank You All!!

[MWJB]

Firstly, what do MM say about the DCR reading you have?

Secondly DCR is probably not the best perameter to judge a choke by, thicker the wire the less the DCR, so what's the MM's mA rating? H & mA rating are what you should be going by, mA will most likely end up a "by product" of the other 2.

5F6A has 2 power tubes (2mA per tube @ idle, allow 10mA each) and 3 preamp tubes (drawing 3-4mA per tube at idle, even if you allow 10mA per tube that's 50mA tops) so you would have to have a significantly underrated choke if it were to fail in normal use. 60mA+ is plenty...lower DCR suggests a higher mA rating.

Not a particular fan of MM, but what makes you think that their spec is wrong?

[tonecat]

I called MM today and they said the choke should read around 45 ohms DCR but they didn't have a mA rating for it which I thought was strange. My test of 39 ohms is not off by much according to their specs. I still think I am going to give the 5 H Heyboer a shot to see what if any differences there are between the two. Not to mention that the MM is really big and actually rubs on one of the speaker frames in the 4 x 10 cab. The Heyboer is smaller and wound on paper and is close to the specs for amps like the super reverb. If anyone has experimented with choke values and has any info, please let me know. I can't imagine there will be much difference between 2.84 H and 5 H especially with the loose tolerances that chokes generally have. Thanks Again and Happy Thanksgiving!!