Notes on the Harvey-Wells TBS-50. October 2004: Bought the radio in October 2004. However, had no power supply for it, so it sat until I got a power supply. I opened up the transmitter and checked the tubes. All tested fine on my Sylvania Type 140 tube tester. Cleaned it up a little too. Wasn't terribly bad. February 15, 2005: On February 15, 2005, my APS-50 arrived. Checked the tubes and they were fine. Noticed an extraneous wire in there, so disconnected it (I hope it was extraneous... the schematic showed no such thing). One of the caps had been replaced with a new one. Hooked it all up and made sure the knobs & switches were set correctly. Put in a 3571.5 kHz xtal for 14286 kHz. Fired it up. No smoke- which is always a good sign. Saw the 807 tube glowing inside, which is another good sign. I let the tubes warm up for a little while, then tuned a nearby receiver to 14286 to listen for carrier. Threw the standby switch to tramsmit and nothing was heard (however, no popping or fire either, so I'm at least staying even). The meter on the radio didn't move nor did the power meter hooked up. Switched it back to standby. Rechecked all knobs & switches (all correct) and put the switch to transmit again. Nothing. Tried the other antenna connector on the back (yes, there are two) and still nothing. Turned off everything and searched the Internet. Found some curious pictures of the TBS-50 (the original)... no clear thingy in the lower left of the front and only one antenna connector. My radio had been modified. Once open, the clear plastic thingy on the front appears to be some sort of lamp holder (with no lamp or any discernable function). In checking the two antenna connectors, found that they led to a relay. There is no relay on the schematic. Found that this is a mod that was outlined in: Amateur Service Notice #10: Mobile Operation of Bandmaster Series Transmitters. At least now I know what was going on. After careful thought, decided to deactivate this mod (as it wants the mobile power supply instead). Clipped the wires and put tape over some of the ends. Also replaced the original SO-259 socket. It was painted red and also gummed up & had quite a bit of corrosion. Cleaning it would've been more work than it was worth. According to the description in the mod, it appears that I have an early model TBS-50. The new socket was hooked up to C16, as in the schematic (not to the relay). Checked to make sure the mod was non-operational and severed the PTT wire that was added from the mic jack to the rear octal connector (this was also a mod. The wires used for the mod were clearly different than the ones used by the manufacturer). Put the crystal back in and left the case off. Powered the stuff up and let the tubes warm up. Set a nearby receiver to 14286 again and it went off. Batteries died. Put the thing on the charger and went to a different radio in another room and cranked it up. Once all was set, flipped the switch to transmit. Neither meter moved and nothing was heard on the radio. Apparently its still not working. Tried phone, CW, and other things. Still nothing made the meters move nor a signal on the radio (not surprising there was nothing on the radio as the power meter was indicating zero power out). After a little bit, there was some popping from the APS-50. I turned off the TBS-50 immediately and the popping stopped. Let things sit for a minute and tipped over the APS-50 and there was no apparent damage (could not tell where the popping was from... from a tube or from underneath). Turned the TBS-50 back on and the popping resumed. Turned it back off. Was really hoping it would work once I took the PTT mod out, but obviously something else is going on (or more specifically, not going on). Luckily, there's not much to this thing, so should be able to get it going. While working on this tonight, was listening to CHWO 740 on my National NC-183D and NC-173 (173 is nearby the workbench and the 183D is in the room with the computer. Workbench (aka bar) is about halfway between the radios). Was really quite fitting to work on this radio while listening to this music. Perhaps some lucky testing potion is needed, but not tonight. February 24, 2005: The main problem is that the HV from the APS-50 is not getting to anywhere useful in the radio. The HV comes into the radio and is found on TP2 screw 8. However, that's where it ends. It goes nowhere else... seriously. The only voltage the tubes are getting are for the heaters. The schematic clearly shows this. And interestingly, the examples of the jumpers on the schematic don't connect to screw 8. So how in the world does the power get distributed?!? Have a feeling the schematic is wrong with regards to the jumper settings (which is identical to the TBS-50B,C,D). After much thought and research, it appears that the TP1 & TP2 jumper settings for the TBS-50B,C,D are not the same as for the original TBS-50. And I also believe the settings on the TBS-50 schematic are incorrect as well. The B-D models have the HV coming in to screw 11 instead. 8 is used for something else. Big question... can I just run a jumper wire from 8 to 11 on my model safely? Unfortunatley, this detail is quite elusive. Also, the 10k/2W resistor between TP2 10 & 14 is open. September 6, 2006: I have not forgotten about the little fella (altho I glad I wrote the above details, as I forgot those). Got a few radios on the bench right now (BC-348-P, Hallicrafters S-20R, Hallicrafters S-40A, Hallicrafters SX-28, Swan TV-2, a couple of others). Really want to get the TBS-50 going... perhaps a quick project for the near future. February 19, 2007: Looked closely at the jumpers on the back. Noticed in the schematic for the TBS-50 (not the B,C,D), the resistor should be 39k not 10k. Tried 39k resistor (24k + 15k) and still some smoke. Only about 5W output on 80m & 10m. Found that I have probably 3 bad xtals, so can't check most of the rest of the bands. Rewired the jumpers for 300V - 6V heater operation (put my APS-50 on lo). Still a little bit of smoke from the coil on 80m. Flipped the switch to hi and more smoke. Poor coil. The xmtr is connected to my 50 ohm dummy load through a power meter. The jumper should run from 8 to 11, otherwise no HV will be flowing. Still don't know why coil is smoking. But at least making slow progress.