Unisonic digital answering machine with voice, very neat.
This I got for free along with a Phone Mate microcassette answering machine. Request if you want to see a vid of the Phone Mate, too. ... https://www.youtube.com/watch?v=0oQeorecsBc
A portable reel-to-reel tape recorder by JVC (Japan Victor Company/Victor Company of Japan).
This machine was also known as the JVC Stenotape, which I believe exported units were. This one, however, is the Japan model. Being the Japan model, it is more original in a way, it bears the "His Master's Voice" iconic dog and phonograph, and Victor name. Find out more of the history of JVC and is relation to the Victor Talking Machine Company on the Wikipedia article on JVC:
https://en.wikipedia.org/wiki/JVC
Also, the inside of the battery compartment reveals Japanese text, more confirming this to be the Japan model, not the exported model.
This unit is built like a tank, very solidly constructed with an ALL METAL case, hardly any plastic. The machine is all idler drive, not a single belt, so the drive mechanism is very reliable and long-lasting. Even the aging rubber is good enough to get a grip.
Only service I had to do was clean and lubricate the idler for the rewind, but I also went ahead and replaced the "tired" electrolytic capacitors in the amplifier and motor circuit. The originals were OK, but not registering as low and ESR as a fresher one.
The amplifier uses six germanium transistors, PNP of course, and the recorder uses DC bias and DC erase. The layout of the PCB is very simple, and all capacitor axial leaded. Manual level control. Frequency response is not the best, and is somewhat comparable to telephone quality. Although not hi-fi, this recorder has good intelligibility for voice, even at the lower speed of 1 7/8 IPS (4.8cm/s). It's a great dictation recorder. Though with its good speed stability, does well for music, sans the limited frequency response.
I really love this recorder's style, all metal constuction, and so-forth. A fun recorder to use and show off to other people, recording their voices as they speak!
The beautiful website, N's Page:
http://ns-page.com/recorder/recorder.html
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https://www.youtube.com/watch?v=Ml9QisyW9bk
This is a very special recorder, made in Lithuania, from 1978. According to another video of the same model, they were even made as late as 1985 or so! Anyone who knows when they stopped making this model recorder please let me know. Also if anyone knows when they began production of this model.
This unit runs on 12VDC, typically one supply for the motor, the other for the electronics. Of couse both can be powered together, but with some added interference noise from the motor.
This unit runs at 1 7/8 IPS only, and is AC bias.
This is a 3-head unit, but oddly, you ONLY can monitor the tape when recording. Even to set the level (with a neon light) you have to have the tape running and wait the slight delay for the signal to come back when playing from hte play head.
The music at the start and when demonstrating is by LOGIC SYSTEM, not by me. It belongs to them, not me.
HOWEVER the song that says "LONWORKS" in a robot voice I made as an experimental song, the sound heard as the instrument was a repeaded playing back of digital program data from the EEPROM out of a LONWORKS card for an rooftop air conditioning unit! Honors to the LON communication protocol...
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https://www.youtube.com/watch?v=0qjhXpvElKo
Playing a few recordings from the reel that came with my USSR (Soviet-Lithuanian) reel-to-reel tape recorder, the P-180-M (П-180-M), manufactured by VILMA, a company that not only made tape and wire recorders (and as far as I can tell from their website, still MAKES WIRE RECORDERS TO THIS DAY!!!!!), but also made secret devices for used by the KGB, and the Soviet Air Force and Navy!
VILMA Factory Website:
https://translate.google.com/translate?hl=en&sl=ru&tl=en&u=http%3A%2F%2Fwww.petrovsky.nnov.ru
Crypto museum article on VILMA:
http://www.cryptomuseum.com/manuf/vilma/index.htm
These may be KGB or other spy or military recordings, or perhaps just someone at his home wanted to record his telephone calls. I don't know, as I don't speak Russian.
Did someone mention the nuclear program? Kinda sounded like it at one point, but I'm not sure.
This recorder runs at a single speed, 1 7/8 IPS (4.8 cm/sec). AC bias, AC erase. Manual level control. 3-heads, but ONLY can monitor the playback head during recording, so the operator is absolutely certain that recordings are taking place. Setting the level is by means of a neon indicator (why not use a nice meter movement‽). I think that overdrive is shown when the neon lights up, so level is set with the play volume knob set to the red marking, then recording level set where loudest sound lights the neon, of course after a short time delay, as the tape travels from record head to play head. This is what I believe is the proper way to set the level. Correct me if wrong.
I have finally built a little amplifier module for this recorder, and installed a battery holder for a set of three 18650 Li-Ion cells to power this unit at about 12VDC. The unit originally used some proprietary or hard-to-find batteries, so 18650's work nicely instead. I can then charge them with a separate Li-Ion charger I built. The 12V goes from the external power input jack (this time used as a power output jack) to power a separate 1.5W transistor amplifier, which has its volume preset, so the recorder's (only designed for headphones or external amp I believe) volume control would control amplifier volume. The little amplifier works nicely. The amplifier's circuit schematic is here:
http://www.redcircuits.com/Page33.htm
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https://www.youtube.com/watch?v=VYUUGkhC4lc
Project 37 on the Tandy/Radio Shack 200-in-One kit. Built on breadboard. Adjusting the variable condenser adjusts the volume of the sound. Why is that? Reactance. Lower the capacitance and that will increase the reactance, the resistance the capacitor applies to AC signals.
Remember, I am not the author of this circuit design or the text in the manual!
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https://www.youtube.com/watch?v=DOOS3I7hItg
Here is a "Videophone" conversation between me and a very amazing man, Jordan, the SpeakerFreak95!!
This is an analogue television transmission from a TV modulator hooked up to a video camera. The transmission is picked up by a 1980s Sony Watchman handheld B/W TV, and the audio (for phun) is through two old Bell telephones, wired in series with a not-the-best-filtered wall plug-in transformer. Here, you can hear the classic sound of the phone with its carbon microphone.
To watch Jordan here is simply an amazing, mind-bending experience!!
MIND=BLOWN
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https://www.youtube.com/watch?v=erbCqjmMCUg
This is a simple and fun project you can build, even without much electronics experience! The circuitry is incredibly simple, and uses no transistors or any kind of complex amplification circuitry. It simply passes a current through a carbon microphone, into a speaker, on/off switch, and then back to the AA battery.
You will need:
Two old handsets (with screw-on mike and speaker covers--this type uses the required carbon microphone)
One AA or AAA battery
Battery holder (optional)
An on/off toggle switch
Long 4-conductor cable (no shielding necessary)
Some shorter connecting wires
Wire stripper
Flat-head screwdriver
Recommended:
Soldering iron
60/40 Rosin core solder
If you have no soldering experience, you can wrap the wire onto the appropriate switch contacts. If no battery holder is available, you can tape the wire ends to the battery terminals, and hold tight with a rubber band.
I have built one of these (now long-since disassembled) in the 6th grade, except using 8-ohm speakers, no switch, and a 9V battery). Also, around that time, I had made a (now disassembled) PA system using a "Powerhorn" horn speaker from RadioShack (8-ohm), a carbon mike, and a 12V battery. It worked well. Point is, is that the carbon mike projects can be extremely simple, fun, and useful.
I apologize for the video glitches. My computer was being slow.
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https://www.youtube.com/watch?v=TkxSDKJ1b7Q