Hello again list, I received a few responses to my last post including and some photos of the plate choke from the original QRO HR2000 amps. They seem to be close wound with something like 120 turns
Author: Victor Rosenthal 4X6GP <k2vco.vic@gmail.com>
Date: Mon, 8 Nov 2021 10:04:55 +0200
One procedure to test and adjust a choke is this: 1. Short it in place and check for resonances in the ham bands with a GDO. The short makes it possible to find series resonances. Leave the tube and
U can also buy the ameritron plate choke from Tom Rauch, W8JI...at his new business website... CTR engineering.com. These are a more precise, tested for resonances etc. I know several folks who tried
The W8JI business website is https://www.ctrengineeringinc.com/ 73, Bob, N6TV _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman
MFJ has never been known for their quality control, regardless of which of their brand names are involved. 73, Jim K9YC _______________________________________________ Amps mailing list Amps@contesti
I'm sold on the RF choke from RF Parts https://www.rfparts.com/rfc3.html Replaced RF choke (Mess) of Alpha 89 with this choke and performed great, all bands. Well not the CB band, didn't try that. 73
It went up into flames and smoke when I tried it on 18.15MHz in my L4B. 73 Peter, DJ7WW I'm sold on the RF choke from RF Parts https://www.rfparts.com/rfc3.html Replaced RF choke (Mess) of Alpha 89 w
Date: Fri, 12 Nov 2021 11:45:57 -0800 From: Jim Brown <jim@audiosystemsgroup.com> To: amps@contesting.com Subject: Re: [Amps] < Message-ID: <95d62c19-7d9e-f068-5fda-28d08e167c73@audiosystemsgroup.com
Here is some food for thought. In both my SB-220 and my HL-2200, I added a 10 ohm 10 watt resistor directly below the stock RFC and prior to the bypass capacitor to ground. Its purpose is to protect