591
Item nr.
External digital tuning
| Production | The Netherlands, 2024.
Price was 16. |
|---|---|
| Bands | LW through SW. |
| Semi- conductors | Cymometer. |
| Cabinet | Plastic. |
| Power | AC 230V@2.3W. |
The little unit has banana jacks on the back, and I made a cable to connect it with a radio. The best point is the grid of the oscillator triode. Connect the "hot" (red) wire with that pin, and the black wire with clip to an earth nearby. For the Noval ECH81/UCH81, use pin 9. For the Locktal ECH21/UCH21, use pin 3. For the Rimlock ECH42/UCH42, use pin 4, and be careful not to short anything with the sharp and tight shielding around the tube base.
Energy consumption of this unit depends, of course, on the tuned frequency, because the red LED segments draw current. Tuning 1111.1kHz, the unit consumes 1.58W, while at 8888.8kHz, it takes 2.40W. Listening Radio Paradijs at 1467.1kHz takes 1.99W, but slightly mistuning to 1467.1 kills four segmants and takes just 1.87W.
| Obtained | 1/2024 from own construction. |
|---|---|
| Condition | 8. |
| Value (est.) | 15€. |
You can take out all you don't need, and are left with a nice box that perfectly fits a six-digit cymometer, and readily built-in 6V power supply. Cymometers can be connected to the oscillator of a radio. You can make a soldered connection (with small capacitor); experiments with capacitive coupling by a cap over the mixer tube worked out unreliable. My Philips BX480A has the 6300kHz point marked precisely on the dial. Clearly, connecting anything to the oscillator circuit may introduce capacity and decrease the frequency. Connecting the meter to the triode plate, this 6300kHz point tunes to about 5900kHz, a decrease of 400kHz (or 6%) that causes a definite misalignment and decrease in sensitivity. Connecting the meter to the triode grid decreases frequency to 6284kHz, just a decrease of 16kHz that can be safely ignored. This experiment indicates that the triode grid, not plate, is the point to connect the Cymometer.