Cassette player/recorder SONY TC150B

14. April 2021 ingmarsretro Leave a comment

The Sony TC-150 is the newest, old member of the collection. Once again purchased as a defect device, this baby found a place in the workshop. After a quick inspection, it was immediately clear that the ravages of time were gnawing and, as is often the case, the drive belts became brittle or decomposed. Otherwise, the device is in perfect condition, hardly any scratches and damage to the case. The battery compartment was also clean. There are four belts of different lengths in the device.

Suitable replacement belts can be obtained, for example, from a large electronics store that is represented in Austria by six megastores. You will quickly find what you are looking for under the name “drive belt range” and “1.1mm edge length”. Replacing the straps is less quick. Here you should take at least half an hour and carefully take the drive apart.

The main circuit board must be removed in order to access the pulleys or to be able to unscrew them further. However, this is only possible if some lines are unsoldered. Only then you can fold up the board. Once that’s done, you can unscrew the retaining plates above the pulleys. They form the backing of the flywheels (capstan shaft). On this occasion, it is advisable to check the capstan shaft for dirt (due to belt wear) and damage, or it should be cleaned. The pressure roller must not be neglected either. In this model, both were in great condition. The pinch roller was neither glazed and brittle, nor contaminated with tape wear or shrinked. So I could put on the new straps. The main belt from the engine is put on with a rotation of 90 °. Here you should note the installation position of the old belt, if it still exists, or at least do a short test run after fitting the new belt.

If everything turns again (and especially in the right direction) then the assembly can be done. Solder the wires again, screw the circuit board and the repair is done. To have this man a test cassette, here are some parameters, such as tape speed or the tracking of the tape head, which are given and adjusted if necessary.

the VU-meter for recording level control to as battery meter

Technical data of the SONY TC-150:

Vendor:                            Sony
Type:                                         TC-150 (Europa) bzw. BT-50 USA
year of production:           ca. 1977 – 1982 (according to various sources)
Modell kind:                          portable Cassette Corder
Hauptprinzip:                      NF-Audio
                                                     Magnetbandaufzeichung/Wiedergabe
tape speed:      4.8cm/s
heads:                  1 recording-/playback head
                                                     1 earase head (Permanentmagnet)
semiconductors:                8 tranistors, 5 diodes, 2IC´s, 1 FET
Power          :                   Outputpower: max 360mW
                                                     Powerconsumption : max 9W
Supplyvoltage: battery 4×1.5V AA, or accupack BP28
                                                     12V Caradapter bzw. 6V 4W wallplug
operationtime:                    2.5h at continous recording
Speaker:     dynamic 5cm Lautsprecher
Abmessungen:                    174 x 29.5 x 113 mm (BxHxT)
weight:                              ca. 769g

retro technology

Mini-TV Broksonic

14. April 2021 ingmarsretro 2 Comments

This beautiful, small, new piece of technology from the eighties has been added to my collection. It is a small tube radio receiver with radio part called CIRT-2097T from the manufacturer Broksonic (according to Internet research it is an US company). The device I received with the attribute “defective” quite cheap on a flea market platform. So I thought, the risk can be taken and risk a repair attempt. What great things can not be broken – if it’s not just the picture tube.

After a short functional test with the plug-in power supply, it soon became clear that nothing was working. No picture – no sound, no nothing. Since the device also has a battery compartment, I next wanted to try to feed the power via the battery terminals to see if there may already be a problem. And there it was already – the problem. The battery cover was almost impossible to get off, it held as glued. After some back and forth, I got the lid but then non-destructive and it revealed the cause of “jamming” or better “gluing”. There were still batteries in the battery compartment (probably for 20 or more years). They were in a bad condition, totally corroded and leaked. In part, the outer coat of the cell was corroded and no longer available. Oh dear – I thought, hopefully the leaked dielectric did not move inside the unit and did damage there. There was nothing left for me to do but to disassemble and check everything. And then the evil manifested itself:

About a quarter of the TV board had come in contact with the battery fluid. And the stuff has done a great job, etched away almost all the traces and leads from components.

So I first tried with PCB cleaner to remove all the crystals and the rest of the battery juice to get a closer look at the damage. A few random measurements with the ohmmeter quickly showed that many traces were severed. So it did not help, the tracks had to be uncovered. Only then would a reasonable repair possible.

Rough cleaning with the brass wire brush

With a rotating brass wire brush, I then began to remove the etched areas, remove the remains of the solder resist and expose the copper traces.

After the rough preliminary work had the glass brush ran. Only with that it was possible to remove all paint and corrosion residues and finally expose the traces. A tedious job …

… but finally it was possible to uncover and repair all damaged areas. Some resistors and capacitors also had to be renewed because their leads were also in poor condition.

After the repair, a bump test could then be carried out – lo and behold, there was no further error and the device was working properly again. So I was able to protect the repaired area of the board with solder varnish from renewed corrosion and reassemble the device.

Finally, here is an overview of the technical data:

vendor:                            Broksonic (US-Firma New York)
type:                                  CIRT-2097T
year of production:   ca. 1982
model:                               TV+FM Empfänger portable
receiverprinciple:       Superhet
screensize:                     2 Zoll SW Bildröhre
bands:               AM, FM, SW (Radio), VHFI,VHFIII,UHF (TV)
                                              AM: 535-1605kHz
                                              SW:3200-9700kHz
                                               FM:88-108MHzTV:
                                               VHF Kanal 2-13(US), 2-12 (E)
                                               UHF Kanal 14-83(US),21-69(E)
supply:                               battery or accu, AC with adaper
supplyvoltage:              accu 6V, battery 6×1.5V AA
speaker:           dynamic 16 Ohms speaker
outputpower:              150mW
dimensions:                  150x53x202 mm (BxHxT)
weight:                             ca 1.1kg

Retro - Consoles

NES Classic Mini : Off with exorbitant prices

14. April 2021 ingmarsretro Leave a comment

The Nintendo company launched the Nintendo Classic Mini game console and put it on sale in 2016. It is a revival of the original 8-bit game console Nintendo Entertainment System from 1983 (release in Japan) and 1986 (release in Europe). The original NES console has sold around 61 million times and was replaced in 1992 by the SNES (Super Nintendo Entertainment System) a 16-bit console. The popularity of the Nintendo consoles is apparently so great that the new edition was sold out shortly after its release with a retail price of around 60 euros. Here traders sensed the big deal and offered the devices on Amazon, ebay and the like at sometimes horrendous prices. Even now, almost a year later, they are still not available for less than 100 euros. And Nintendo doesn’t produce any other units either. Instead, the same game began with the revival of the SNES series in miniature.

But there are other ways you can get a miniaturized version of this console for a lot less money. For a few euros you get a case called NESPI CASE, which corresponds to the NES CLASSIC MINI, but with one big difference: you can install the computer yourself in the form of a Raspberry PI. This opens up countless possibilities to use emulator software to recreate your own consoles using software. The NESPI case has an integrated 4 port USB hub and a LAN Ethernet connector that leads the connections of the Raspberry PI to the outside. Two USB ports are arranged in such a way that they serve as controller connections. The other two USB ports and the Ethernet connection are located under the device flap, where the game modules were once inserted. The device is equipped with a power switch with a power LED and a reset button.

The housing is supplied with pre-assembled adapter boards. The screws for mounting the Raspberry Pi and the housing shells are also included in the scope of delivery. A small included Phillips screwdriver and a piece of paper with assembly instructions make things even easier.

The LAN and USB ports of the RaspberryPi are routed to the outside via the cables and plugs on the adapter boards. Once the plug connections have been made, the RapsberryPI board can be screwed into the housing. Optionally, a 5VDC fan with the dimensions 30x30x10mm can also be attached to the housing cover using locking lugs. A two-pole pin header is available on the circuit board for the power supply of the fan. Once everything has been installed and connected, the upper part of the housing can be screwed on.

The software can now be set up. I prefer the images from retropie or recalbox. More information can be found on the relevant websites. Once the desired emulators have been set up, you only have to transfer the game files, the so-called “Roms”, that is, binary copies of the game modules of the original hardware in a .bin or .rom or .iso file etc. to the SD card or USB Copy the stick and integrate it into the “EmulationStation”. And you’re ready to go. The USB controllers in the NES look are also available for just a few euros from China …

NESPIE with NES-Nachbau “ChinaController” attached

clocks and watches, electronics hobbyist

VFD clock with date, day of the week and sound

14. April 2021 ingmarsretro Leave a comment

I received a new kit for vacuum fluorescence display from Günter (gr-pojects). Thanks a lot!

It is a clock with Type IV-11 vacuum fluorescent display tubes for hours, minutes and seconds, and an IV-18 tube for date display, and IV-3 for displaying the day of the week. The clock consists of a mainboard with power supply, CPU, MP3 module and driver blocks for the tubes. The time is set and synchronized via an externally connected DCF-77 receiver. Later, the board will be extended with a real-time clock circuit. The power supply for the entire circuit comes from a small plug-in power supply with 12V / 1.2A. The total power consumption is about 450mA. As a special feature, the clock has a small MP3 sound module with MicroSD card slot. This receives from the microcontroller via the serial interface every quarter of an hour a corresponding command to play an MP3 file. Thus the quarter of an hour is signaled with a “gong beat”, half an hour with two and three quarters of an hour with three “gong strikes”. At the full hour, the corresponding time is announced.

The entire circuit is built into an aluminum-acrylic housing. All fittings are milled and screwed. A video of the structure and the function can be seen below:

retro technology

Philips “Sonate” Philetta Euro280

14. April 2021 ingmarsretro Leave a comment

In the years 1968 to 1970, the radio receiver was built with the inscription “Philetta Euro 280” by Philips. It is a small multi-band receiver with transistor equipment. The type designation 12RB280 / 30 with the inscription “Sonata” seems to be another version of this model. In any case, I have dug up the version “Sonata” – once again from the depths of the Kellergefilde – and after superficial cleaning connected to the mains. Immediately after switching on, the scale illumination lights up and a loud 50 Hz hum can be heard from the loudspeaker. Increasing the volume level adds some noise. So switched to the FM band and searched for a station – and lo and behold, it works. Only the buzzing disturbs. Otherwise, the device works without any major problems. To find the cause of the humming, you begin with the troubleshooting as usual in the power supply.

The rear panel is quickly removed and the power supply unit, consisting of a, mounted on a support plate transformer including rectifier and filter capacitors removed. Now, without using the oscilloscope and the multimeter, you can immediately see where the ravages of time have left their mark. The two electrolytic capacitors do not look quite healthy anymore.

A quick measurement of the voltages brings certainty. The DC voltages have a decent ripple, which causes the “hum”. So the function of the electrolytic capacitors to smooth the DC voltage is no longer, or poorly, given. A measurement of the capacities confirmed that. So I renewed the capacitors.

Immediately after switching on, even before I had the probe at the measuring points, a noise was heard without “humming”. The oscilloscope image now showed a clean DC voltage – almost no ripple. The receiver worked again very clean, without disturbing background noise. That was apparently the only mistake.

Technical information:

The main principle of the receiver is a superhet (according to the superposition principle) with an IF of 460/10700 kHz. The waveband of the receiver:

long wave
medium wave 1 (520-1400kHz)
medium wave 2 (1400-1600kHz)
shortwave
UKW

The output stage has a power of 3W, which is converted into sound energy in a dynamic loudspeaker with permanent magnetic excitation. The case is made of plastic and has the dimensions 43×17.5×10.5cm with a weight of 2.4kg. The receiver is supplied with 220V / 50Hz mains voltage.

retro technology

Walkman City Bummler from the 80s

14. April 2021 ingmarsretro Leave a comment

From the early 1980s comes the “City Bummler” a mobile, portable cassette player – in short a Walkman. At that time, I received it as a Christmas present during my middle school years. The special feature of this device was a built-in microphone and two headphone ports. So you could listen to music in pairs and if you wanted to say something without having to remove the headphones (or to reduce the volume), so you had to press only an orange colored button and the intercom was active. The device was sold as a low-priced “replica” version of the first Walkman from Sony, the TPS-L2 which came on July 1, 1979 on the market. The citybummler was distributed by UNIVERSUM via the source mailer.

City Bummler with a self made coverplate after the original got broken

The device was delivered in a box with headphones, cassette pocket and carrying case with strap. For operation, three AA size 1.5V batteries were needed. The volume control is carried out with two separate sliders, so that each channel can be controlled separately. Unfortunately, the city loafer has not passed the last 35 years quite unscathed. Over time, the cassette cover was broken off, which I then replaced in my youth with a homemade tinplate lid. At some point I did not like the case color and I painted the device green. (or I just had green paint at hand). At least the “loafer” still exists and it works too.

I was then on the Web in search of a well-preserved, in the original state city loafer. However, the offer is extremely low and the few offers on online auction houses are not interesting because of the immense shipping costs.

But a compromise and at the same time a new piece in the collection is the FELLOW FE-1 Walkman. I got the most cheap and fully functional on a second-hand stock market.

The Fellow is also a clone of the Sony TPS-L2. It differs essentially in the arrangement of the keys of the drive.

Retro electronics kits

science kits PHILIPS EE 2000 series

14. April 2021 ingmarsretro Leave a comment

Another electronics kit from my youth is the Philips EE series. It dates approximately to the years 1976-1979. The box presented here is the EE2050. Unfortunately, this is no longer the original that I recorded back then, but a version bought on eBay. But this is a real collector’s item, because the box has never been recorded.

The boxes (EE2003 / 41/50/51/52) under my custody have unfortunately not survived the years. Since the modular system was designed in such a way that all components were “free”, ie not riveted to any sockets (just as they were also used in industry), I always used them. If I needed a resistor or capacitor quickly, the kit had to serve as a “donor”.

Befestigung des Bauteils auf der Grundplatte — Fixing the component on the base plate

The concept of the modular system: It consists of a perforated plastic base plate through which a hairpin spring is inserted. This hairpin spring in turn holds a spiral spring. Now, between the hairpin spring and the upper end of the coil spring, the connection wire of the component can be clamped.

The components themselves are contained in the box as they are also commercially available. An exception here are only the transistors and transformers. They are mounted on a small printed circuit board, which facilitates assembly and also protects the component itself from mechanical stress.

In the final stage, the box consists of two bolted base plates, which in turn are bolted to a control panel. In this media console then turn capacitors, rotary potentiometers, buttons, bulbs and a speaker place. The number of experiments to build is also huge. The manuals are very well structured. They describe the basics of DC technology, as well as the operation of the circuits.

Here is an excerpt from the inscription of the electronics box. Note the gender-oriented spelling 🙂

Wonderful world of electronics – a mysterious world that every boy wants to get to know and understand. This electronic kit gives him the opportunity to easily gather his own insights in this field. The box contains a richly illustrated instruction book and over 150 items – e.g. 10 resistors, 5 capacitors, photocell and transistors. Thanks to the clamping system, the young electronics builder can assemble these parts completely independently and without prior knowledge to the following functional devices:

Burglar Alarm Systems, Amplifiers, Automatic Parking Lights, Humidity Indicators, Acoustic Relays, Morse Exercise Machines, Brightness Controls, Timers, Others – a total of 21 electronic devices and many interesting circuits.

With additional boxes the possibilities extend to the MW radio with loudspeaker. Proper engineers work with the same parts: all the boxes in the Philips Elektronik series are equipped with the most modern parts of today’s electronics in their original form.

Mechanics hobbyist

The steam engine

14. April 2021 ingmarsretro Leave a comment

The following piece is about 40 years old model steam engine from the manufacturer Wilesco. (Thanks to Manfred for the loan for the media preparation). The model consists of a highly polished and nickel-plated brass kettle, which is built into an old copper-colored boiler house with brick pattern. Heating is done with a dry spirit burner located under the boiler. The pressure vessel has a spring safety valve and a “Domdampfpfeife”. The pressure line is led to a single-acting pendulum cylinder, which in turn drives the crank and the flywheel on it via a connecting rod.Trockenspiritusbrenner.

The entire model is mounted on an iron plate. In order to be able to drive mechanical models with the machine, a pulley is mounted on the shaft of the flywheel. Since the model has been stored in a carton for the past forty years, a few small jobs have been done. Piston and crank were stiff and had to be cleaned and re-oiled. The crank was a bit out of alignment with the flywheel shaft.

The seals of the “Domdampfpfeife” and the pressure relief valve were also brittle and hardened and were replaced. Here I was able to use a suitable punching tool made of “new” old gasket material to knock out and insert two new gaskets. Now the model was a little bit freed from the dust of the last years and cleaned and a start attempt was nothing in the way.

Now the spirit burner could be filled with a small piece of dry spirit, which was probably even older than the machine itself. At least the original box looks like this:

Invalid Displayed Gallery

retro technology

analogue multimeter – Unigor 3n

14. April 2021 ingmarsretro Leave a comment

From the years from 1964 comes the analogue multimeter Unigor 3n from Norma, respectively Goerz-Metrawatt. It was characterized by the large measuring range of 52 measuring ranges, all of which can be selected with just one selector switch. The measuring mode and polarity reversal is realized with a push-button switch. All measurements (except the 10A range) are possible on just one terminal pair.

The measuring mechanism is a “clamping band measuring unit” with a very good vibration resistance and low self-consumption.

The internal resistance for voltage measurements is a maximum of 4MOhm in the highest measuring range (see photo technical data). The voltage drop in current measurements is given as 12mV in the 120uA range and 120mV in the 30A range. The measuring accuracy is 1% for DC and 1.5% for AC measuring ranges.

Like the Unigor 6e, the 3n model is also equipped with various safety features.

The power supply of the multimeter takes over a 1.5V mono cell.

Technische Daten — technical specification

retro technology

analogue multimeter – Goerz Minitest

14. April 2021 ingmarsretro Leave a comment

The Goerz multimeter, model: Minitest FE5101 dates from 1969 and was manufactured by the company Goerz Elektro Ges.m.b.H from Vienna.

Introductory sentence from the operating instructions: “It is a multi-measuring instrument, which is particularly suitable for service work in the field of news and radio technology and electronics due to its small dimensions and low weight as a pocket instrument It allows the measurement of: equal and AC voltages, DC and AC, resistance, capacitance and frequency. “

The internal resistance is 20kOhm for DC and 4kOhm for AC. The achieved accuracy is 2.5%

As overload protection, the moving-coil meter is equipped with antiparallel-connected diodes.

In this model, the measuring ranges are not to be selected by a selector switch, but each individual measuring range is designed as a socket on the device. The sockets themselves are suitable for 2mm banana plugs. The power supply for the resistance measurement comes from a 3V dry cell battery (type 2R10 duplex battery).

For the measurement of the capacitance with this device an external voltage is necessary, because here no own alternating voltage generator is installed. This said external voltage is the 50 Hz mains voltage which is connected to the device via its own supply cable. So a capacity measurement up to 500nF can be achieved. Measurements greater than 0.5uF are no longer possible due to the low measuring frequency. Goerz supplied a polystyrene transport case for storage and transport.

Ingmar's Retroblog

Cassette player/recorder SONY TC150B

Mini-TV Broksonic

NES Classic Mini : Off with exorbitant prices

VFD clock with date, day of the week and sound

Philips “Sonate” Philetta Euro280

Walkman City Bummler from the 80s

science kits PHILIPS EE 2000 series

The steam engine

analogue multimeter – Unigor 3n

analogue multimeter – Goerz Minitest

Technik & mehr von damals und heute