Audio recorders

Aiwa TP-30

Aiwa TP-60R

Andy Gard Recorder

Answer ATR-102

Apolec RA-11


Assmann TS 10

Concord F-20

Concord F-85

Crown CTD-2200

Dictaphone Dictet

Dictaphone 4250

Dictaphone model 848

Dictaphone "OMEGA"

Dictophone KGB "Sobesednik"

Dokorder PT-4H

EDI model M-75B

Edison Envoy Model 1

Electron 52D

Electronica M-401S

Electronica M-402S

Electronica M327

Emerson Wondergram


Fanon-Masco FTR-2

Fi-Cord 1A

Fi-Cord 101S

Fi-Cord 303

Fi-Cord 300A

Gray Audograph D6

Grundig EN3 Luxus

Grundig DeJur Versatile III

Grundig Stenorette 2000

Globe-Corder GT-101

IBM 224 Dictating Unit

Juliette LT-44

Lanier VIP/C

Lloyd's 8 track player


Memocord K60

Memocord mini K177



Minifon Mi51

Minifon Attache

Minifon Attache-Speaker

Minifon Hi-Fi

Minifon Liliput

Minifon Protona Special

Minifon P55 "Plexi"

Minifon P55 L (1957)

Minifon P55 L (1960)

Minifon P55-Speaker

Minifon_wrist watch_mic

Mohawk Midgetape 44

Mohawk Midgetape 300

Mohawk Midgetape 400



MS-61 - Flight Recorder

National RQ-8100

Norelco LFH 0085/54

Norelco LFH 0095

Olympia DG 402

Olympus Pearlcorder L200

Panasonic RQ-115

Panasonic RQ-212DKS

Panasonic RQ-SX56

Panasonic RQ-SX97F

Philips EL 3302

Phono TRIX 88

Playtape 1200

Pocket Corder MC-2

Reporter 5

Ross Mark-55

Sanyo Micro-Pack 35

Sanyo M2580K

Sony BM-17 Dictator

Sony TC-5

Sound Machine "Hokie Pokie"


SoundScriber 200

SoundScriber 200 B

Sputnik 401

Spy Tape Recorder

Steelman Transitape

Stenotape TR-711

Stuzzi Memocord 304 B

Tefifon Holiday BK-59

Telefunken 600

Telmar T-100


Topaz D202



яхта-1ћ (Yacht)/явiр-1



Televisions, video

Akai VT-150

Akai VC-150


Electronica-video VMP-1



Electronica L1-08

Panasonic TR-1030P

Sony AV-3400

Sony AVC-3400

Sony SL-F1E & TT-F1E

Sony Watchman FD-30A

Sony Watchman FD-40A


Tube radios

Emerson 508

Motorola 56L2

RCA Victor 54B2

RCA Victor BP-10

Sterling LS-4

Tourist PMP-56

United Deluxe RN-5




Minifon_wrist watch_mic

Andy Gard Recorder

Olympia DG 402

Dictaphone Topaz D202

MS-61 - Flight Recorder


Other rarities

Detective Dictograph



Motorola M75

Pentacon six TL

Tube Tester I-177


V/A - Meters

First transistors USSR


My works

Tube stereo cassette player

Tube Microcassette recorder

Tube "Electron 52D"






RussianAudio recorders Televisions, video Tube radios NEW Other rarities My works


Olympia DG 402




Used Google translator

     Olympia DG 402. This is probably the latest model of the recorder with recording on magnetic disks. Judging by the markings on the details it was made in 1974, when the cassette recorders were no longer a novelty. Of course this recording format has its advantages, but nevertheless, the mass production of such a device in the mid-70s is surprising. Its advantages include the ability to quickly find the right place of recording and the ability to send the discs by mail, but you can make only 10 minutes of recording on such a disc.
     The recording technology is similar to the tape recorder, but the recording is made not on a magnetic tape, but on a plastic disc with a ferromagnetic coating, on which there is a spiral groove 0.3 mm wide, along which the working part of the magnetic head moves. Probably serial production of the Olympia DG 402 was not long, and this model is quite rare, but in the previous decade, these devices were relevant and in demand. The first such voice recorder was Telefunken 600, which began production in 1962. Also in my collection there is a later and technology model Assmann TS 10, but they are all structurally similar.
     Interestingly, the microphone from the Telefunken 600 of the earliest model with a non-standard connector is fully compatible with the Olympia DG 402 recorder in the mid-1970s. By the way, this is not just a microphone, it works both as a speaker and as a remote control with the functions of turning on the recorder, turning on the playback, recording, and reversing the disc, analogue of rewinding. The recorder itself has a volume control - a recording level combined with a switch, an electric motor speed regulator, and a red button for quickly erasing a record from the entire disc. When this button is pressed above the dial, a permanent magnet extends to the width of all grooves, and when the disc is rotated, the disc is erased in a few seconds.
     The device measures 295 x 215 x 68 mm, weighs 3 kg, is powered from 220 V, 50 Hz, and has a recording function from the phone. I will add that the plastic magnetic disks Olympia DG 402 and Telefunken 600 are the same, and differ only in marking, in the first case the inscription "Olympia", in the second case the "Telefunken" logo. The electronic circuit is assembled on 11 transistors and a TAA511 chip. The amplifier uses 8 transistors BC3198 (5 pcs.), BC239C (1 pc.), BDY34 (1 pc.), And a transistor labeled S122T. The engine speed regulator uses transistors AC187, BF194, and a transistor labeled S122T.
     The device works fine, and it's really convenient to use. Especially useful was the function of reverse rotation of the disc, since this voice recorder was intended for dictating texts, and the reverse function was needed to quickly repeat the last words for the convenience of printing text on a typewriter.

Photos can be enlarged

In the kit there is a nice cover, but unfortunately there is no original microphone. I use a microphone from a similar voice recorder Telefunken 600, they are fully compatible

     Magnetic disks Olympia DG 402 and Telefunken 600 with a diameter of 155 mm are almost identical, and differ only in marking. In the first case, the inscription "Olympia", in the second case the "Telefunken" logo. Telefunken disks also have two holes, apparently for use in dictaphones with a different disk fixation. In these recorders, the disc is fixed on a rotating table by pressing it down into a hole with a diameter of 38 mm

     In the illustration to the left, the parameters of the groove of the Olympia DG 402, Telefunken 600, Assmann TS 10 magnetic disk are used. These discs are also used with the similar Traveller and Kurier dictaphones manufactured by Telefunken and AEG, respectively. However, with the original Assmann TS 10 discs, the diameter of the hole is different, but the groove parameters are the same. On the reverse side, all the disks are black. 

This recorder is made in Germany, like other similar Telefunken 600 and Assmann TS 10

In the photo above, the patch panel with the "Phone" - "Microphone"

The recording is from the edge to the center of the disc. When the tone-arm approaches the center, contacts that include a sound signal are closed. In the extreme right position, the tone-arm is fixed by a spring, the contacts of the engine control circuit are activated, and it stops. To move the tone-arm, you must press the control knob from top to bottom, while the head rises above the disc, and you can freely move the tone-arm to any position. If you move it to the extreme right of the fixed position, the disc retainer rises and you can replace it.

The photo below shows how to quickly erase information from the disk with the help of a permanent magnet

The electronic circuit of the Olympia DG 402 is much more complicated than the Telefunken 600, which is assembled with only 5 transistors

The design of the magnetic head unit is the same as that of the Telefunken 600. In one case, the erasing and universal heads are assembled. The width of the working part is 0.25 mm. Resistance of the universal head 250 ohms, erasing - 33 Ohm. Details on the construction can be found on the page Telefunken 600

I got the dictaphone in the original package



(c) 2022 -