01-28-2018, 10:10 AM
Arran,
Yes all HFs are ultralinears. 22 and 35 models are the same, using the same transformers with 22 using 6L6 and 35 using EL34 tubes.
HF-22 is widely considered an EICO marvel as somehow this amp sounds super nice despite being very simplistic; many think that the output transformer is the reason.
Some folks mod these itroducing a choke in the filter.
I intend to leave the amp original.
I was surprised to find out the amp uses less current out of the 5U4 than the 690 radio, so the ripple rating of the Panasonic caps I use for my radios is well in excess of the required one.
The stock caps to my taste are underrated in the WV departmet, being 450V for the 435V B+ shown in the sch. I use 500V 22uF 450mA caps, so two in parallel to make the required 40uF will provide ample 900mA for the 200mA estimated ripple.
I feel lazy doing restuff but maybe I will.
Yes all HFs are ultralinears. 22 and 35 models are the same, using the same transformers with 22 using 6L6 and 35 using EL34 tubes.
HF-22 is widely considered an EICO marvel as somehow this amp sounds super nice despite being very simplistic; many think that the output transformer is the reason.
Some folks mod these itroducing a choke in the filter.
I intend to leave the amp original.
I was surprised to find out the amp uses less current out of the 5U4 than the 690 radio, so the ripple rating of the Panasonic caps I use for my radios is well in excess of the required one.
The stock caps to my taste are underrated in the WV departmet, being 450V for the 435V B+ shown in the sch. I use 500V 22uF 450mA caps, so two in parallel to make the required 40uF will provide ample 900mA for the 200mA estimated ripple.
I feel lazy doing restuff but maybe I will.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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