The preamp will be mounted right next to the two 6L6 modulator tubes on the bracket holding the Pi-filter components. My version does not have the two electrolytic capacitors on the chassie like the original version, other than that, they are identical.Ī closer look at the modulator preamp schematic To the left below is what the original microphone preamp looks and to the right is my homebrew version, before it's installed. In 1940 John Wells joined the company, the name was changed to 'Harvey - Wells Electronics Company' in march 1940. Harvey & Wells sold a kit for such a modification and holes were already drilled in the chassie to accomodate the preamp. In addition to the load vari-cap, the plate vari-cap doesn't look original either. That 5 one on Ebay has so many extra holes it looks like swiss cheese.
Nice addition to many Harvey Wells rigs, as usually they are missing. This was attached to a TBS-50C, but is untested and sold as-is.
#Harvey wells bandmaster series#
I'm hunting for the D model with the built-in pre-amp for a crystal mic. Harvey Wells Bandmaster VFO for the TBS-50 and Senior series transmitter. a bandmaster at Harvey, organized for the Second North Dakota Infantry. The schematic below is for the TBS-50 D-version with a 3 tube microphone preamp. That's why I'm looking at a Bandmaster, just 17lbs. in Norway Lake, Wells County North Dakota before he joined the armed forces.
#Harvey wells bandmaster manual#
Unfortunately this VFO was beyond salvation when I bought the TBS-50 so I decided to build my own VFO from the original Harvey & Wells schematic with a single 6AG7 tube.įurthermore my plans were to build a replica of theHarvey & Wells microphone preamp to enable me to use more modern microphones than a carbon type microphone.īelow is the schematic from the original manual of my version of the TBS-50, designed for a carbon microphone for AM. Nils never had the original VFO from Harvey & Wells, instead he built a VFO of his own design in an old TU-5 chassie. Finally, after a years of persuation I was able to buy it from him, and I was determined to put it back on the air one day. When Nils SM2BPE became Silent Key in 1982 this transmitter came into the hands of a good friend of mine who kept it for many years in his basement without ever putting it on the air. Nils was an active radio amateur and willing to Elmer me into the hobby.Īfter seeing the TBS-50 and and HRO 7 with the matching speaker and a Vibroplex key on Nils' shack table it was easy to dump my plans for a CB career to instead focus on learning CW to become a licensed radio amateur. My father took me for a visit to his colleague Nils as my father had noticed my interest in wireless radio. It used to belong to my friend Nils SM2BPE (SK) and I first saw it in his shack in 1968.
Basically this transmitter made me decide to become a radio amateur. This particular Harvey & Wells TBS-50 transmitter has a special place in my heart. Renovation and modification of my Harvey & Wells TBS-50 CW/AM transmitter
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