Our story begins somewhere in the year 2007, the actual date isn’t as important as that of the event occurring.

For it was on this day Brian O’Connor (KA2CGB) made a trip to Ohio to visit a friend. It was at this time Brian became in possession of a rather unassuming and slightly grotesque, Heathkit SB200 that “been in his (friend’s) barn for a long time”, Mr. O’connor recounted to me, one fine evening, via electronic mail exchange. It was destined to be modified for 6 meter but little did Brian know that day would never come. It was somewhere in Brian’s domicile that the SB200 sat. Untouched, year after year. Eventually, it came to live in the corner of a RARA storage unit, long forgotten until the year 2022.

In June of 2022 the SB200 was placed on the free table at the RARA Hamfest. It sat there for some time as passersby dismissed its unaesthetic appearance. The face-plate was long removed of its namesake manufacturer, let alone any identifying marks. It’s paint long forgotten and only known to those with the keenest of memory.

There was one gentleman who passed by the table only glancing at the poor thing but he looked at it several times throughout the day. 

This is his story.

I came upon the boat anchor noticing it several times throughout the day. It was near the end of the day that I decided to take the thing home.The faceplate barely had any paint left. I knew it to be a Heathkit but wasn’t sure exactly what it was. “It’s an amplifier”, Brian said. “They’re good for modifying for 6 meters”, he added. I was curious and decided to take it home. 

As you can see it was a long way from being on the air again. I was delighted that the tubes were still there and appeared intact. Upon closer inspection I discovered that all that dust and grime was mostly superficial. 

Time to do some research. What is a SB200? I watched numerous videos, obtained PDF copies of the assembly manual. Etc. 

This is where I warn you that vacuum tube devices, especially amplifiers can have plate voltages in the area of 2KV and higher. You should take precautions when working around High Voltages. 

Since lead times have been extended, it was off to Harbach Electronics to bring this rig up to standards. I purchased the new power supply board, soft-start for said power supply, and the soft-key mod so that My Elecraft K3 could key it without blowing itself up. While the Elecraft K3 can key an amplifier up to 200VDC it can not do the -200VDC required by the SB200.

After copious amounts of contact cleaner, alcohol (denatured and medicinal), canned air, and agitation the first cleaning was complete. It’s starting to look better but definitely not ready to go on the air. It would take many more cleanings, disassembly, cleaning, and polishing, and cleaning again to get the unit like new.

I cleaned up the case and painted it a “matte deep gray”. Along the way I repaired the dents and dings to give it a better than new look.

Along with the previously mentioned updates, I also replaced the original fans with 2 120VAC 80mm fans capable of 43CFM each, no sense in converting to DC and creating a possible noise source if I don’t have to. All the capacitors were replaced with new. The resistors were replaced with the appropriate type.The parasitic suppressors were NOS carbon composition to keep the top looking period correctish and other compositions can cause issues. The visible aluminum surfaces were cleaned, sanded, and polished. A new HV wire was installed good for 45KV. A new 12 AWG 20 amp cord set was added. 

During my restoration I found that the amplifier was last serviced on 12/3/86 as evidenced by the etching left behind. Sadly, there was not a callsign. 

The variable capacitors and inductors were in really good shape. There was no sign of pitting or previous high voltage arc over. Likewise the ceramic band select switch while tarnished...