Heathkit SB-220/1 Super Large Capacitor Bank + HV diode board. Kits with parts
If you are rebuilding a Heathkit amplifier and the filter capacitors are looking a little shabby this is for you. I finally made a PC board for the larger Capacitor bank that I have been putting into SB-220s. This kit has over double the original capacity of the original bank to give the old girl a bit more pep. It has to go in sideways compared to the original capacitors but because the caps are smaller, there is actually more room for ventilation.It did require a new sheet metal housing, that is also included (professionally made, not by me). This more than doubles the original capacity of the filter bank and makes for a very clean install.
This board includes a number of improvements over the original. It has connectors to allow the front panel to be removed or extended during service. The original pads are still present and can be used if connectors to the front panel are not desired. >A string of 1N5408 diodes for the voltage doubler (larger than the originals).
>A string of 1N4007 diodes to replace the original Zener, including capacitors to filter the voltage. >A string of 2meg 1% resistors to divide the high voltage for the voltmeter. >A limiting resistor to provide the current for LEDs on the panel meters if you decide to do that. How this happened: The combination of being retired and being a ham leads to a lot of tinkering.The internet is full of advice, some good, some bad, and some absurd, so I selected a reasonable subset of information and did a respectable job of rebuilding a couple of amplifiers. But along the way the tinkering spirit led me to lay out a couple of PCBs to clean up some of my work.
So when the boards eventually came in, the chassis went back on the bench and went through another revision. And like so often happens, I realized that the boards could be a little better and set out to design another set. Well, when you order printed circuit boards, you don't get just one.There is no intent here to compete with the other boards (W7RY and others), they do a good job and provide a reliable source for much needed replacement parts. If you need this I assume that you are qualified to work on high voltage circuits and will take all safety precautions. I made every effort to do a good layout and provide quality parts, however, I can take no responsibility for your work or any damage to your equipment. If you are not familiar with electronics and especially working around high voltage, this may not be for you. The pictures are for information, you do not get a SB-220 or assembled boards. You will get just the boards, the parts needed to populate them and a copy of the schematic. The pictures are examples and are from several different amplifiers. The components you receive may be a different style but the values will be correct. Assembly should be obvious, but I provide some basic instructions.
- Brand: AG6YJ
- MPN: Does Not Apply