Showing posts with label OPTONICA. Show all posts
Showing posts with label OPTONICA. Show all posts

16 May 2020

OPTONICA RT-6905 (1980) - Can I push that Button ?

cassette deck

The OPTONICA RT-6905 from 1980 is basically a one box combination of the Optonica RT-9100H cassette deck and AD-200TH programmable quartz timer unit. The cassette deck section features a 2-motor, dual-capstan, closed loop drive system that provides constant back tension on the tape for optimum tape-to-head contact, quartz -locked PLL servo capstan motor that ensures super-accurate tape speed, and Optonica's new microcomputer -controlled tape tension adjustment system that automatically optimizes tape tension before all playback operations. The Optonica RT-6905 uses a 4-head system with Dual Sendust recording, playback and monitoring (APMS sensing) heads. Test tones are provided for adjusting record sensitivity and bias, used in conjunction with the level display and the tape/source monitor switch. Then, to maximize user control, this unit provides Sharp's unique APMS (Auto Programmable Music Selector) to allow complete freedom in programming tape selection playback order, plus APSS (Auto Program Search System) for one-touch skipping and repetition of songs.

In the lower section can be found a programmable quartz timer unit with programming capacity of up to 42 automatic operations per week (absentee recording and musical alarm set-ups). There is a special synchronization of the cassette running time counter with the tape transport mechanism. The time counter can be used to keep track of either the running-time or the remaining-time of a cassette and includes a pause function that stops the counter during breaks. An infrared remote control is also provided for seat-side control of all tape transport functions, including recording and APSS, while additional rack handles were sold separately. Manufacturer's specifications. Frequency response 30 Hz to 20 kHz with Metal tape, Flutter 0.038 percent W rms, Dimensions 430 (W) x 211 (H with adjustable legs) x 371 (D) mm, Weight 15.8 kg. Original sale price 1,600 USD.

cassette deck

cassette deck

cassette deck

cassette deck

cassette deck

cassette deck

cassette deck

19 January 2017

PCM Adapter - Old Digital Audio Format

Before the introduction of a standardized format to record digital audio to a tape (the DAT recorder) the practice was  to use a PCM adapter (pulse code modulation) connected to a video recorder to record the digital audio signal to tape. The PCM adapter was connected to a video recorder using the video in/out of the unit in order to record the PCM coded audio digital signal where normally the video signal is recorded. The reason to do this was that a linear tape recorder did not have sufficient bandwidth to record large volumes of PCM data while video recorders were available both for studio and home use and the rotary video heads used in a video recorder had sufficient bandwidth to do this. Most video-based PCM adaptors record audio at 14 bits quantization, and a sampling frequency of 44.056 kHz.

pcm adapter
PCM connection diagram

First generation PCM adapter

pcm adapter
SONY PCM-1 1977

pcm adapter
Technics SH-P1 1979

pcm adapter
DIATONE PCM

pcm adapter
SHARP RX-1 VC-6300 1979

Commercial models

pcm adapter
Aurex XD-80 1981

pcm adapter
Aurex XD-60 1981 (right)

pcm adapter
DIATONE D-102 1982

pcm adapter
SONY PCM-F1 1981

pcm adapter
Technics SV-100

pcm adapter
SONY PCM-501 1984 / 553ESD 1985 / 701ES 1984

pcm adapter
Sanyo PLUS 5

pcm adapter
Sansui PC-X1 / PC-X11 1988

Dedicated audio players using VHS video tape

pcm adapter
Technics SV-P100

pcm adapter
HITACHI PCM-V300 1982

VCR with PCM audio

pcm adapter
Aurex TOSHIBA PCM-D1

pcm adapter
Aurex TOSHIBA PCM-D1

Prerecorded PCM audio on VHS tape

pcm adapter
Mobile Fidelity Sound Lab prerecorded PCM (digital) audio on VHS

More vintage audio @ www.1001hifi.com

23 October 2016

3 HEAD cassette deck rarities

vintage audio

In this article we take a closer look to some of the rarest 3 head cassette recorders. They were either market specific models or were only made in low numbers so they hardly ever show up for sale on the second hand market.

First in this line-up is the OPTONICA RT-9100H. Optonica was a brand name used by SHARP for their high-end audio gear. This model is not necessarily rare but is definitely one of the less known 3 head recorders....with 4 head. Yes it is a genuine 3 head recorder with monitor function however there was a 4th head that recorded signals to the tape for a sophisticated music search system. It was available as OPTONICA RT-9 in Japan, OPTONICA RT-9100 the rest of the world, while the black version was OPTONICA RT-6905 that came with an additional programable timer unit.

cassette deck
OPTONICA RT-9100H

cassette deck
OPTONICA RT-6905

cassette deck
OPTONICA RT-9

The next model is from Austria and it was made by eumig (Elektrizitats Und Metallwaren Industrie Gesellschaft mbH. in Wien). Before eumig became known with their version of a rebadged Alpine, the eumig FL-900 or the famous eumig FL-1000 they made this 3 head model called the eumig Metropolitan CCD. Released in 1977 this cassette deck uses heads from WOELKE (Germany) mounted on a full die-cast chasis. Instead of the usual rec/playback sandwich head this model uses an independent playback head while the recording head is sandwitched together with the erase head and there is azimuth control for the recording head.

cassette deck
eumig METROPOLITAN CCD

Moving to the next model there's a 3 head cassette deck from a turntable specialist. This is the Lenco C 2003 Direct Drive dual capstan 3 independent head cassette deck from Switzerland. (699 USD 1977)


cassette deck
Lenco C 2003

Talking about turntable specialist, here's the one and only Thorens PC-650 3 head cassette recorder from 1979.

cassette deck
Thorens PC 650

Part of the slimline 777 system from SIEMENS this is the SIEMENS RC 777, a 3 head cassette deck with Sendust heads. This deck could be sourced from SANYO as the smaller SIEMENS 666 system uses rebadged SANYO units. 

cassette deck
SIEMENS RC 777

Another 3 head cassette deck is the ITT HiFi 8025 from 1979 (more detail here)

cassette deck
ITT HiFi 8025

Last but not least here's a 3 head cassette deck from the former communist block. This is the UNITRA MDS 625 from Poland, a deck with dual capstan mechanism, 3 ferrite heads and dual speed (4,75 and 9,5 cm/s)

cassette deck
UNITRA MDS 625

For more vintage audio visit www.1001hifi.com
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27 February 2016

BIGGER = Better ?


These are some of the BIGGEST cassette decks ever made. Were they better than a regular sized deck ? In some cases yes, they were hiding a complex mechanical construction and sophisticated electronics to achieve the best possible sound. Let's take a look at the models and the years they were made.

The AKAI GXC-570D  was first manufactured in 1975 and it features 3 heads and 3 motors.


The eumig FL-1000 was made in Austria in 1979. This is a highly regarded cassette deck.


The OPTONICA by SHARP RT-6906 from 1981 was a 3 head machine with an extra head for a sophisticated track search system. 

The PIONEER CT-A1 from 1979 is a 3 head unit with a complex tape calibration system. Briefly sold as Linear Phase 7000 a company that was recently acuired by PIONEER.


A big and beautiful cassette deck from Norway. This is the TANDBERG TCD 3004 from 1980. 


A not so well remebered model is the TEAC A-860 from 1976.


A two box solution from Technics. This is the RS-9900US from 1977.


Here is something interesting, something you would not expect. These are two models from 1977 made by UNITRA from Poland. They are the UNITRA M-601SD and the 3 head UNITRA MDS-624. 


Finally the BIGGEST of them all but never manufactured. The LUXAN X-3K, only shown as a prototype. With this system the aim was to completely extract the tape from the cassette and run it on a free and precise tape path. 


See more cassette decks that were actually manufactured here.

03 March 2015

Compact Cassette and the Digital age





The history of the Compact Cassette begin in 1963 when PHILIPS presented the first compact cassette recorder, the EL 3300 as a dictation machine. This format quickly became very popular and soon the Compact Cassette became a competitive Hi-Fi stereo audio format. Being so popular and widely available there were other technological fields that choose the Compact Cassette for various purposes. Here are some examples.

In 1975 a KODAK engineer, Steve J. Sasson builds the World first still image Digital camera. It had a resolution of 0.01 megapixel captured by a CCD image sensor and stored on a Compact Cassette. It took 23 seconds to record a black and white photo. Images were played back from the Compact Cassette into a computer and displyed on a television set.





In 1985 the same Compact Cassette was used, this time by TOSHIBA under it's japanese brand name Aurex to store digitized images captured by a video camera. The picture below shows the two components of the digitising-storing equipment. At the bottom is the digitising unit and on the top is a regular cassette deck from the Aurex/TOSHIBA range (Aurex PC-X66AD) using a Compact Cassette as storage. 


The last model we see here is again an audio equipment, but this time it's a digital audio recorder that is using a Compact Cassette. This OPTONICA by SHARP unit was made by SHARP in 1985. The OPTONICA RT-X5 model was using a 9.5 cm/s speed to record digital audio in 14 bit / 44.1 kHz sampling frequency format. Aparently it was only a prototype.

                             


The shown equipments only made it as prototype units but, the Compact Cassette was fairly popular in computer data storage systems, such as military aircrafts.....and that's classified information. 
(Hush hush, you haven't heard it from me)

Discover more about the Compact cassette reading the history of the first