Also to FB group Vintage Transistor Radios I finally drew the line and said I’m finished fiddling with this Zenith Royal 200 and put it back together. I got it without knobs or handle, and with all the transistors missing. It’s not pretty, and the speaker cone is warped and sounds bad. This is the
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Continued from post 2020-01-15 I dug through my drawers and boxes of transistors and found a bunch of MPSA56 PNP general purpose on tape, and put them into the LO and mixer. I think they helped slightly – they are lower minimum fT than the 2N3906s. I adjusted – optimized – the trimpots I had
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I’m thinking of pulling up the end of the 100 ohm and looping the lead a few times through the ferrite bead. If that still doesn’t stop the ringing, I’m thinking about replacing the bead with an RF choke. Every time the ringing is reduced the reception gets better. I checked to see if I
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This photo is a detector diode that was broken during replacing the electrolytic capacitors. The lead on the top was twisted, apparently putting stress on the glass package. I replaced it with a 1N270 germanium diode. comment from fb group Vintage Transistor Radios Did you notice that the leads are magnetic? They stick to the
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I posted this a few days ago.https://m.facebook.com/groups/606087512820068?view=permalink&id=2638214152940717 Now I’ve replaced the capacitors in another one very similar, a DE LUXE. It’s not quite as complete and in as good a shape as the Encore. What surprised me was that some of the electrolytic capacitors were bad (measured open) and the symptom was no sound whatsoever
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From FB group Vintage Transistor Radios There are really only two types of germanium transistors in older radios. One is for the RF and IF stages and has low collector to base capacitance. The other is audio and can handle a few hundred milliwatts. I recently replaced the germanium audio transistors with silicon, with change
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From FB group Building Transistor Radios Willie Barnett I see from the schematic that this is a reflex regen. They did something else that is very seldom seen, the volume control acts not as a normal variable voltage divider, but instead as a variable shunt load across the secondary of the driver transformer. This is
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From FB group Building Transistor Radios Willie Barnett I see from the schematic that this is a reflex regen. They did something else that is very seldom seen, the volume control acts not as a normal variable voltage divider, but instead as a variable shunt load across the secondary of the driver transformer. This is
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From FB group Building Transistor Radios Jim Glover You asked about performance. There are factors unrelated to either type that affect the performance, one being the type of wire used. If Litz wire is used it has lower losses, and therefore higher Q than solid wire. Same holds true for silver plated wire at HFs.
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From FB group Vintage Transistor Radios OMG, that was so long ago, I could never sort out which one. See, I was born with a soldering iron in my hand, and I fixed so many radios, I could never remember which one was one that I had. Most of the electronics I was given were
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