accessorizing the Sony 2010 receiver
I just dusted off (literally) the Sony 2010
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| a beauty from the 20th century |
the idea is to use it for listening to code practice. This was a portable shortwave receiver by Sony in the late 20th century. It covered 150 kHz to 30 MHz, FM and air band, was synthesized, had memories, 4 timers, a very nice machine.
Of course it had faults. The JFET preamp wasn't protected when an external antenna was used so most of them got damaged resulting in a deaf radio. There was a recording output but it was mic level not line level so that could be inconvenient. The LED backlight for the LCD display is kinda weak. The synthesizer has chunky 100 Hz steps but still has a lot of "chuffing" as the frequency is varied. The internal clock/timer is not super accurate, losing enough time that the radio is tuned to WWV regularly to reset the time.
But these are all quibbles for a fine design, well made. There aren't any menus, everything is handled via the keypad and the tuning knob. The four timers are easy to program to a time, duration (15, 30 or 60 minutes) and frequency. The synchronous AM detection is neat, I used it to listen to select the best sideband if there was an interfering station close in frequency. Compared to the analog dial shortwave receivers I had been using the synthesizer was a dream, no guessing as to the frequency, no need for crystal calibrator, just dial it up and there the station is.
Over the years I've used different recorders with the Sony 2010. The higher end cassette decks often had built in microphone inputs along with a timer switch that would start recording when the power was turned on. Eventually I tired of cassettes and bought a Sangean DAR-101 digital recorder.
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| Sangean DAR-101 |
The main accessory I've added is an AC supply, just a basic linear supply but I added a simple current sensing relay. As soon as the Sony 2010 timer turns on the fairly large current used by the 2010 turns on the relay. This relay can drive either an AC output or in the case of the Sangean, a "remote" input.
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| the 2010 power supply, transformer on left, 5V regulator on right |
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| a current sense and relay output circuit for the power supply |
The nice thing about the current sensing relay to turn on the recorder is that only 1 clock is involved, the Sony. I had also tried using an X-10 appliance timer module to turn on the recorder but it's almost impossible to keep the radio and X-10 timer clocks in synch so the recordings often had dead time at the start when the Sony clock was tardy.
One problem with the Sangean DAR-101 recorder was that although it has microphone inputs, it's impossible (AFAIK) to use them when timer recording. So a simple opamp amplifier was added to increase the microphone level Sony 2010 output to "line level".
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| an opamp amplifier to boost the mic level output to line level for the recorder |
Unlike the Sony 2010 the DAR-101 has tons of menus, also unlike the 2010 the DAR-101 display is nicely lit and easy to see
Another problem with the Sangean DAR-101 is the built-in Nimh battery charging, look at the reviews on Amazon or just take my word that it doesn't work quite right (I remember waking up in the middle of the night due to the DAR-101 power cycling ON and OFF continuously,audibly and visually). I suspect it might be some kind of lack of enough hysteresis or maybe a temperature problem with the voltage reference. In any case I charge the batteries used in the DAR-101 externally now :)
Other problems with the DAR-101 include that the knobs have that kind of plastic that gets sticky over time, yuck. Also, the DAR-101 has a rotary dial "tuning" control for making menu selections that I never liked, maybe it's my arthritic fingers or ? but I just never liked it.
Otherwise the Sangean DAR-101 is a nice unit but maybe a little old fashioned. Once a person gets used to the random access ability of digital MP3 players it's hard to use the fast forward and reverse buttons of the Sangean. So I'm always on the lookout for a replacement recorder, until then it's easy to sneakernet the SD card to a different mp3 player.
Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm