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On the parasitic choke i have read either a 36 or 47 ohm 2 watt. I have 30 ohm & 68 ohm would one of them be close enough? 238

Trying to find the valve of the 2 resistors that go to pin 2&11 and the one that goes to pin 5 & 9 on both tubes. 5&9 are wired straight across the 2 tubes, so you only have 1 resistor. Also i can only turn the -vdc down to -157 vdc . I put a NTE5156a zener 100v x 5w. The pot someone put...

Changed the choke, amp back too working. Still only get 1 peak. Have jumped the coil in different numbers, but still no 2 peaks. Taking a break on this one. Going to re cap my Maco super 75. 238

So i thought i would check the other Brute75. It had no mesh, so i spread the coils no change. I mashed the coils close together it blew the choke below the coil. It could be i let coil touch the choke,not sure. 238

I checked an this one has 2 peaks not to far apart,

When i started out it had no mesh. I spread the coils an i have a little mesh. I will have to check about the 2 peaks. Thanks. 238

I was trying to make sure we where on the same page. Thanks. 238

Yes. I moved the tune control to the front. Changed the coax inside to 316 grounded on both ends. I have 4 or 5 of these little Maco's/ Brutes. Some of them have the plate coil tapped at 4 coils. The Brutes tune across all 12 coils. Do i need to change this or dose it matter? 238

The tune knob i am talking about is the one on the front right corner of the amp marked tune. The other plate tune is inside the amp. The one i am turning is the one on the front. All the way to the right is low at about 10 or 15 watts it has no hum. But as you turn it up the hum starts. I never...

If it is an AC hum what do you do about that? The transformer is putting out 867vdc. Do they just go bad internally from old age. I can relate to that. 238

I changed the cap to 100ufx350v. I had changed the 47ufx450v caps out to 80ufx450v. When i turn the tune down to about 10 watts the hum goes away, but as i turn it up the hum comes back. I reckon i need to take to someone with a scope. 238

The cap is 22uf x 250v. The bias is -161 vdc. When i worked on it years ago i put a resistor in place of the wheel. I checked the ohms of the wheel an then put a resistor in its place. 238

I have noticed on my Super 75 the coil between the tune & plate control has been tapped back so you only adjust a cross 4 coil. The Brute 75s adjust a cross all 12 coils. If i turn the tune all the way to the right the hum gets lower as the power gets lower. But i run out of adjustment. The...

Well i have changed all the caps except the ssb cap. Changed the coax inside to 316 grounded on both ends. Moved the plate control to the front of the case. I still have a little hum in the amp, when i transmit, my voice covers it up when i talk. I have noticed on my Super 75 the coil between...

Still trying to find out if i need to add a parasitic choke to the 75?

You can use a 8950 to check it with. Find a used one , long as it is not bad, could be one that is 50% or so. Just to test with.

Ordered the caps & already got them. The Brute 75s do not have the wire wraped resistor at the top of the tube. Should i add one?

Not sure what cap to use to change the metal cap.