Category: ‘Techno’

Re-Birth of SONY STR-343L

2011/02/02 Posted by UL


This nice piece of vintage SONY was bought as “working with some distortion in one channel”. As a matter of fact, the one channel which was supposed to work was working as exciter – it oscillated at some 700kHz – 1MHz. The other one, with “distortion”… Well, I can not say it was working at all. The picture below illustrates the “sine” wave at output…

The voltage at all pins was checked and appeared not to be correct at all.
At this stage the decision to do a recap was made as well. So, one visit to electronic component outlet later the works started with disassembling, re-capping, replacing.

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Categories: Techno

Heavy Metal

2011/01/18 Posted by UL

It seems one can find anything anywhere. This afternoon was dedicated (at least 15 minutes of it) to optical pickup (easily available KSS-240A) replacement. The device in question was a SONY CDP-790 CD player, my father bought it off the German ebay for, like, 1 EUR. It was sold as defective and it was. Well, not defective, but it wouldn’t work without laser replacement. So, Off goes the cover. What’s this metallic sound?

Obviously THIS washer does not belong in here…
A little later and a new laser in place…

In order to check is the new pickup working, I tried to insert headphone jack in the respective opening in front panel. Sadly, it didn’t want to go IN at all. That’s because the place was occupied … with a tip of another jack, stuck in the connector.

The resulting two pieces of metal not belonging to the player are pictured below. The player works properly now.

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Categories: Personīgais, Techno

To Sinus or Co Sinus

2010/12/07 Posted by UL

Hi! I am safely back from the shark infested area of the Red Sea, this is the reason why there were an absence of posts. This season is rather busy. However I managed to start works on my latest ES series collectible – the MosFET SONY TA-F590ES. I was surprised to find out it does not seem any different from 570ES, 505ES and 606ES – the same chassis, the same (more or less) boards. Of course, output stage is somewhat different for models with bipolar transistors, but otherwise…. once again we must deal with dirt and oxidation problem. The inter-boards connectors and input selector, volume attenuator are so dirty they became a kind of semiconductor. See what they did to nice sine wave I feed into the amp. A knock there, push-pull here and the sinus is once again visible. So… the cleaning begins — once again. More will follow.

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Categories: Personīgais, Techno

Surprise, surprise! (from SONY)

2010/11/24 Posted by UL

The very beginning of the process of SONY TA-F35 restoration was full of surprises. Bought the amp as non working. The usual precautions, dummy load, visual check – and switching on. No smoke, no noise, no blasts. So far so good. 1KHz sine 250mV to the input. LED volume meter showing something. But where the heck is the output signal at speaker terminals. To ensure the signal is delivered to all terminals, speaker mode A+B engaged. I was sure this will switch on BOTH speaker pairs in PARALLEL. Well, I was wrong.

Speakers A ON: Everything is OK.


Speakers B ON: Everything is OK as well.


Speakers A+B: Note the path from speakers B to A ...

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Categories: Savādi gan, Techno

Spīdekļsildītājs

2010/11/11 Posted by UL

Ja reiz ES aizliedz kvēlspuldzes, tad tirgojam 150W apsildes elementus, kas, tiesa, ir ar blakus efektu – spīd! http://heatball.de/en/

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Categories: Politika, Savādi gan, Techno

Stripped to the bone

2010/11/08 Posted by UL

The after hours (I needed to attend a parent’s meeting at my daughter’s school and I had a couple of hours not worth to commute out of town and back in a half an hour) were spent stripping down a nice supplement to my ever-growing SONY ES series collection. SONY TA-F606ES is not so mighty TOTL as 808 or 707, but it delivers real (!) 80w/ch into 8 ohms, has good though basic preamp, headphone out. Solid, understated, classy, and unlike first-gen MOSFET amps, it runs cool. Unfortunately this was stored in some damp wet place for at least a decade. The chassis was covered with … RUST ! Not the Mathias Rust who landed on Red Square back in the 1987 (anyone remember?), but good old iron oxide. Some time later an attempt to use it was made. obviously only to discover the need to apply a cleaning fluid to all switches and attenuators. Now the amp was covered in rust AND oil inside …
I stripped it down and I have a very special kind of treatment in mind for it. More will follow tomorrow. I hope I’ll succeed… ;-)

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Categories: Personīgais, Politika, Techno

USSR Vs JAPAN or SONY reEngineered

2010/11/05 Posted by UL

The first picture shows how it was designed. The second one – much better solution. ;-)
The vintage Russian (soviet) made knob from some unknown semi-military device was chosen to replace missing attenuator knob on SONY TA-F500ES amplifier.
Knob unfortunately was lost together with volume attenuator. The attenuator itself was easily replaced with 100k potentiometer from Argus parts store.
Well. At this stage problems occurred. The original part was equipped with fourth contact or taper for loudness and tone adjustment. It appears this obscure design is impossible to obtain from ALPS or NOBLE or… so, while waiting for new knob to be made, this amp can be used only in non-switchable SOURCE DIRECT mode, as the tone controls does not work and obviously never will. It is possible to add some op amp based tone control circuity to the amp, but I rather will not to.

I do really think my new knob is rather well looking and cool! Isn’t it? ;-)

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Categories: Techno

Atdošu labās rokās

2010/11/04 Posted by UL

… bārenīti – Technics vinila spēlētāju SL-B3. Bez vāka, adatas un siksnas. Dzima tas tālajā 1978. gadā un bija apveltīts ar visiem labumiem – pilnīga automatika, liels, smags disks, klusa mehānika, Audio Technica galva un adata, singlu atskaņojamais adapters… Automātiku es likvidēju pats, jo saplīsis zobrats, kas to piedzen. Adatas un siksnas nebija jau kopš Vācijas. Lietotu, bet normālu adatu es varu pielikt, siksna jāsūta no eBay, vāks ir bezcerīga lieta, bet var jau ar linu sedziņu izlīdzēties… ;-)
Cena – 25Ls. Savas vēlmes un ķengas drīkst iekomentēt komentāru laukā. īstenībā, ja man jau nebūtu vairāki, es šo atstātu kā tīri manuālu griežgaldiņu, jo tonarms ir ļoti labs, S-shape, un pats atskaņotājs labā vizuālā kārtībā (ja neskaita vāku, kura nav).

Bilde nav oriģinālā, pārdodamais aparāts stāv mājās izjaukts.

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Categories: Techno

Technics set SU-Z2 and ST-Z1

2010/11/03 Posted by UL

We would call this a “midi system” now. In 1978 it was entry level state-of-the-art HiFi system, using integral hybrid modules for output stage. As always, HR pics at Picasaweb.

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Fine Tuning

2010/11/03 Posted by UL

What do you do when you need to align the dials of your vintage receiver or tuner? Right, you take old soviet made high frequency generator with the FM feature Г4-116 and attach an unshielded wire to the output. Even the miserable output power of this device is enough to set the dial right across the room. Using three reference points – 88MHz, 108MHz and 100 MHz,, the needle of FM dial can be placed pretty close to the actual frequency. The aligned and restored Technics set pictures will follow shortly.

HF FM generator

HF FM generator Г4-116

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