Working on a Yeasu FT-101EE Converted to 11Meters

[danmcclain]

This radio got shook up in shipping. None of the 3 tubes light up and the panel lights are out. Going to replace the driver tube first. Having a hard time locating the 2 panel lights. These bulbs say "Stanley 16VO15A" on them. These are bayonet type bulbs... Not having any luck finding them... Help please... Dan

 

[Smokinone]

FT-101 Parts

Yaesu FT-101 Parts

ft101repair.com

 

[sunbulls]

I would replace them with a 12v warm white bayonet bulb. They’re commonly used as an automotive replacement. In doing so I would also remove the 100 ohm resistor as shown in the schematic and experiment with a much higher resistor to achieve your desired brightness. To be on the safe side I typically start out with 15K ohms and work my way down. There’s a third bulb with wire leads. It’s not a light, but used as an RF fuse. Hopefully it’s not blown. It's a pain to replace.

 

[Smokinone]

You might try an 1818 bulb. They are 24 volts, but at 16V they would be 0.17A @ about 3 watts. Not sure if the brightness would work for you though.

 

[danmcclain]

I would replace them with a 12v warm white bayonet bulb. They’re commonly used as an automotive replacement. In doing so I would also remove the 100 ohm resistor as shown in the schematic and experiment with a much higher resistor to achieve your desired brightness. To be on the safe side I typically start out with 15K ohms and work my way down. There’s a third bulb with wire leads. It’s not a light, but used as an RF fuse. Hopefully it’s not blown. It's a pain to replace.
View attachment 67676

Thank you for the info.... Dan

 

[danmcclain]

FT-101 Parts

Yaesu FT-101 Parts

ft101repair.com

Thank you for info... Dan

 

[nomadradio]

Is the 11-pin round plug firmly seated in the "accessory" ( or is it "ACC"?) socket on the rear?

There is a wire jumper in the plug between pin 1 and pin 2 that feeds 12 Volts to the tube heaters. Pull that plug, the lights stay off.

We routinely soldered a wire across those two pins inside the radio on that socket just to avoid aggravating complaints later on. It's there so your 6-meter or 2-meter transverter can switch off the power tubes, and use the low-level drive that feeds into the 12BY7 for the transmit converter.

And if someone wanted to use a FT101 with a VHF transverter today, I'd be surprised. The jumper wire would seem to pose only a tiny risk.

Maybe it's that simple. Maybe the "Heater" switch on the front has oxidized contacts and won't complete the circuit.

73

 

[danmcclain]

Is the 11-pin round plug firmly seated in the "accessory" ( or is it "ACC"?) socket on the rear?

There is a wire jumper in the plug between pin 1 and pin 2 that feeds 12 Volts to the tube heaters. Pull that plug, the lights stay off.

We routinely soldered a wire across those two pins inside the radio on that socket just to avoid aggravating complaints later on. It's there so your 6-meter or 2-meter transverter can switch off the power tubes, and use the low-level drive that feeds into the 12BY7 for the transmit converter.

And if someone wanted to use a FT101 with a VHF transverter today, I'd be surprised. The jumper wire would seem to pose only a tiny risk.

Maybe it's that simple. Maybe the "Heater" switch on the front has oxidized contacts and won't complete the circuit.

73

Thank you for the info...I will check that... Dan

 

[danmcclain]

Is the 11-pin round plug firmly seated in the "accessory" ( or is it "ACC"?) socket on the rear?

There is a wire jumper in the plug between pin 1 and pin 2 that feeds 12 Volts to the tube heaters. Pull that plug, the lights stay off.

We routinely soldered a wire across those two pins inside the radio on that socket just to avoid aggravating complaints later on. It's there so your 6-meter or 2-meter transverter can switch off the power tubes, and use the low-level drive that feeds into the 12BY7 for the transmit converter.

And if someone wanted to use a FT101 with a VHF transverter today, I'd be surprised. The jumper wire would seem to pose only a tiny risk.

Maybe it's that simple. Maybe the "Heater" switch on the front has oxidized contacts and won't complete the circuit.

73

Also found the 3rd lamp (RF Fuse) and it tested ok... Dan

 

[nomadradio]

That's the one bulb you never want to see light up.

73

 

[danmcclain]

Also found the 3rd lamp (RF Fuse) and it tested ok... Dan

The 11 pin plug in the back is firmly seated... Dan

 

[danmcclain]

The 11 pin plug in the back is firmly seated... Dan

The 2 panel lights tested bad, so found some 10-30 volt ac/dc bayonet bulbs I'm going to try when the get here...

 

[nomadradio]

Hate to say it, but the next-most likely failure to shut down the tube heaters is the front-panel "heater" switch. Jumping across the lugs on its rear would reveal if this is the holdup.

Or not.

73