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Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery

p.kaczmarek2 3855 19

TL;DR

  • Amator 2B stereo radio (DSS201) is presented as a communist-era Polish receiver, and it differs from the Amator 2 by lacking a tuning indicator.
  • Inside, it uses a 50Hz mains transformer, ferrite antenna, slide-pot PCB, isostat buttons, and CEMI UL1321, UL1601, and UL1211 ICs.
  • It receives long wave, medium wave, short wave, and FM; the AM intermediate frequency is 465kHz and FM is 10.7MHz.
  • The power amplifier uses two GML-026 modules, but the only detailed photo shown is a slightly different GML-026/2 variant.
Summary generated by AI based on the discussion content.
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  • Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    Here I will present another popular piece of equipment from the communist era - the Amator radio, or more precisely the 2B version (DSS201). The Amator 2B differs from the Amator 2 in that it has no tuning indicator.
    Amator 2 allowed the reception of long wave, medium wave, short wave and FM frequency ranges. The AM intermediate frequency was 465kHz and FM 10.7MHz. Details later in the diagram, and now pictures.
    Front and top with the characteristic three vent inserts:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    Rear:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    It is also worth adding that there is a fuse hiding at the bottom of the case to be removed:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    Looking inside:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    Let's start perhaps with the power supply, of course there is a 50Hz mains transformer:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    You can see the fuse and the separate PCB from the slide potentiometers:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery
    PCB, isostat type buttons, tuning scale;
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    CEMI, UL1321, UL1601, UL1211 circuits can be seen.
    Elwa electrolytic capacitors:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    Tuning mechanism and bulb (incandescent, not LED) from backlight:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    I really like the tuning mechanisms on these types of old radios. This is probably because I grew up with much newer equipment. Here you can see how the bulb is fixed:


    .
    Ferrite antenna:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery
    PCB underside:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    However, photos can't show everything. It's time for a bit of documentation.

    Schematic of the Amator 2 stereo:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    UL1321 (dual acoustic preamplifier circuit):
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    UL1601 (stereo signal decoder circuit):
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    UL1211 (AM/FM intermediate frequency amplifier):
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    The power amplifier is based on two GML-026s. GML-026 schematic:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    By the way, I see now that I didn't take a photo of them, you can only see their legs in the PCB photo, so I'll use a photo from another topic:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    The photos above show a slightly different circuit, GML-026/2, but I was unable to find GML-026.
    Source: https://www.elektroda.pl/rtvforum/topic1869247.html

    Summary Summary
    Radio potentially up and running. It's not that bad, spares are still obtainable, even GML-026, will there be a bargain for it? Well I don't know, but I'm happy to have shared another old radio with the forum. If anyone has similar specimens in their collection then feel free to post pictures.

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    About Author
    p.kaczmarek2
    Moderator Smart Home  
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    p.kaczmarek2 wrote 14699 posts with rating 12743, helped 656 times. Been with us since 2014 year.
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  • #2 21071909
    szeryf3
    Level 30  
    Posts: 2046
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    Rate: 672
    I think it was the coolest radio I used in those days. I still feel sentimental about it to this day. I wish I had kept it until modern times.
  • #3 21071931
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14699
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    It is for this reason that I sometimes try to show this type of equipment in this section, even though I normally deal with digital electronics anyway. All the more reason for me to encourage others to post topics in "Equipment Interiors".
    Helpful post? Buy me a coffee.
  • #4 21072017
    _Avalanche_
    Level 7  
    Posts: 20
    Rate: 9
    Where are the 2N3055 transistors from on the schematic of this GML?

  • GML-026 and GML-026/2 are different circuits

    #5 21072021
    Mateusz_konstruktor
    Level 37  
    Posts: 4267
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    p.kaczmarek2 wrote:
    The power amplifier is based on two GML-026. GML-026 diagram:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    By the way, I see now that I didn't take a photo of them, you can only see their legs in the PCB photo, so I'll use a photo from another topic:
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    Source: https://www.elektroda.pl/rtvforum/topic1869247.html
    .
    The colleague is confusing concepts.
    First of all: GML-026 and GML-026/2 are two different circuits.
    At the same time, the radio presented appears to have a factory-installed GML-026/2.
    It is impossible not to mention at the occasion of this discussion the fact that there are two variants of GML-026/2, with standard transistors mounted inside and with the structures themselves mounted inside and for this a different transistor model.
  • #6 21072035
    p.kaczmarek2
    Moderator Smart Home  
    Posts: 14699
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    Indeed, the photo in the linked thread shows GML-026/2 and not GML-026. When I get a chance I will take a correct photo, unless anyone has one to hand?
    Helpful post? Buy me a coffee.
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  • #7 21072150
    tank_driver
    Level 17  
    Posts: 194
    Help: 13
    Rate: 22
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
    These are 2N3055 structures bought with the then valuable foreign exchange, hence the later switch to locally produced power transistors,
    Please, and a beautiful description of 'our' ceramic hybrid:
    http://qann.wikidot.com/hybryd-gml
    EDIT: replacing the picture with a larger one,
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  • #8 21072606
    Anonymous
    Level 1  
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  • Hum only, likely misaligned tuning string

    #9 21072611
    MarekS6
    Level 17  
    Posts: 294
    Rate: 63
    this article came to me perfectly here ;p I no longer need to dismantle what I have to look inside out of curiosity :-)

    Some time ago I told my neighbour that if she had any old electronic equipment to throw away, she could give it to me for parts instead of going to the PSZOK. By old, I mean late 1990s and upwards. How surprised I was when she gave me an Amateur 2 radio last week....

    To be honest, I'm wondering what to do with it - for parts it's "too old" and on the other hand I realise it's such a collector's classic and it's probably a shame to throw it away. Apparently there's one taker for it already, but I'm not hearing from him.

    Out of curiosity, I plugged the radio into the speaker and all I can hear is a hum. And all in all, no wonder, because the radio is probably not tuned (old FM range). In addition, the frequency change knob doesn't have a full range of movement - something must have mechanically shifted inside, probably this string is to be rewound/corrected.


    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
  • #10 21072866
    szeryf3
    Level 30  
    Posts: 2046
    Help: 12
    Rate: 672
    @MarekS6 don't throw it away because it's a shame. A little work and patience and it will play and be a pleasure to the eye.

    And I found something like this and a vintage one in my stash.
    Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery Old Polish radio Amator 2B stereo (DSS201) - schematic diagram, gallery .
  • #11 21072901
    cirrostrato
    Level 38  
    Posts: 4884
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    The power supply reefs from Amators, still quite reasonably priced and in good quantity at auctions, are currently the cheapest source for rewinding into output transformers for SE and PP tube amplifiers.
  • #12 21073048
    James596
    Level 29  
    Posts: 1851
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    Putting the tuning cable on this receiver is something of a nightmare. The design itself seems unfriendly in terms of disassembly. The Zodiac was better done in this respect.
  • #13 21073076
    klamocik
    Level 36  
    Posts: 3043
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    A long time ago I just swapped the frayed line for monofilament, a horrible replacement but not to be outdone.
  • #14 21073125
    kris8888
    Level 41  
    Posts: 6998
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    Mateusz_konstruktor wrote:
    >>21072021 .
    First of all: GML-026 and GML-026/2 are two different circuits.
    .
    But functionally they are identical and can be used interchangeably.
  • #15 21073910
    dzg4
    Level 31  
    Posts: 1696
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    I own the older brother of the DSS201, in the DSS101 I inserted the LA3101 instead of the UL1321, plus the recommended blocking capacitors on the preamp inputs, it has its years and is not Hi Fi for it has a warm and pleasing sound.
  • #16 21074258
    ZbeeGin
    Level 39  
    Posts: 4327
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    p.kaczmarek2 wrote:
    The Amateur 2B differs from the Amateur 2 in that it has no tuning indicator.
    .
    There is also a difference in the schematic, as the preamp is made with only one transistor + UL1321.

  • Different tuning cable mechanisms in Amator versions

    #17 21075125
    kaem
    Level 29  
    Posts: 2611
    Help: 66
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    James596 wrote:
    Fitting the tuning wire on this receiver is a nightmare.
    .
    I put it on in "two" with the service manual at hand and managed. In the meantime I've learned that different versions of the "Amateur" had different cable mechanisms.
    I like it if the internal cable from the socket to the UKF head unit is led with a real antenna cable (here a flat 300Ω). In the "Tosca" and I think also in the "Zodiac", they did it by hackwork (with random cables they had at hand).
  • #18 21077404
    Renegat_pol
    Level 21  
    Posts: 392
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    In the 1980s I had an Amator 3. It had an orange backlight, an indicator on LEDs (red) and a "better", more powerful amplifier on a "pseudo-hybrid" (GML in discrete version, on through-hole components and 2n3055 transistors).
  • #19 21077604
    dzg4
    Level 31  
    Posts: 1696
    Help: 132
    Rate: 360
    If you'd had it when the DSS101 was produced and driven the ZG 20 with it, you'd have been a power demon on the estate :) , beautifully looking with their glowing scales with the lights off in the room. For those years the pinnacle of modernity in its class and availability in communist Poland.
  • #20 21077857
    Renegat_pol
    Level 21  
    Posts: 392
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    :) I had some ZG for this. As far as I remember 25W. But as it was in my teens, it got destroyed :) .
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Topic summary

✨ The discussion centers on the Polish communist-era Amator 2B stereo radio (DSS201), highlighting its technical specifications and historical context. The Amator 2B lacks a tuning indicator, unlike the Amator 2, and supports long wave, medium wave, short wave, and FM bands with AM IF at 465 kHz and FM IF at 10.7 MHz. The radio uses the GML-026/2 hybrid amplifier module, which exists in two variants differing in transistor types, including the use of 2N3055 power transistors. These transistors were originally imported but also produced locally by brands such as Tungsram and Tesla. The tuning mechanism involves a cable that is difficult to replace, often requiring rewinding or substitution with monofilament. The Amator series is valued for its warm sound and collector status, with some users modifying or repairing components like the preamplifier (e.g., replacing UL1321 with LA3101) and noting differences in cable routing and amplifier design across versions. Power supply transformers from Amator radios are also repurposed for tube amplifier projects. The discussion includes references to related models such as DSS101, Amator 3, and other Polish radios like Tosca and Zodiac, emphasizing the cultural and technical significance of these devices in their era.
Summary generated by AI based on the discussion content.
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FAQ

TL;DR: The Amator 2B DSS201 uses 465 kHz AM IF and 10.7 MHz FM IF, and one restorer notes it is “potentially up and running.” This FAQ helps collectors and repairers identify the right schematic blocks, find the hidden fuse, and avoid common mistakes with GML modules and tuning-cord work. [#21071835]

Why it matters: The thread combines photos, schematic references, repair observations, and variant corrections that directly reduce disassembly and parts-swap errors.

Model / variant Visible feature difference Schematic / circuit difference Service note
Amator 2B DSS201 No tuning indicator Preamp differs from Amator 2; one comment notes one transistor + UL1321 Same family, but verify exact board before parts swaps
Amator 2 Has tuning indicator Different preamp arrangement than 2B Useful as a schematic comparison baseline
GML-026 Earlier output-module designation Different circuit than GML-026/2 Not identical internally
GML-026/2 Seen in linked photo and said to be factory-fitted in some sets Exists in at least two internal variants Often discussed as a practical substitute

Key insight: The biggest trap is not the radio itself, but variant confusion: Amator 2 vs 2B, and GML-026 vs GML-026/2. Check the actual fitted parts before ordering modules or following a schematic. [#21074258]

Quick Facts

  • The thread states the Amator 2B covers long wave, medium wave, short wave, and FM, with 465 kHz AM IF and 10.7 MHz FM IF shown in the documentation section. [#21071835]
  • The mains supply uses a 50 Hz transformer, and the fuse is hidden at the bottom of the case, so safe opening starts from underneath rather than from the front panel. [#21071835]
  • The audio and radio IC set visible on the board includes UL1321, UL1601, and UL1211, corresponding to the preamplifier, stereo decoder, and AM/FM IF amplifier blocks. [#21071835]
  • The power amplifier uses two GML modules, but commenters stress that GML-026 and GML-026/2 are different circuits and that some Amator receivers were factory-fitted with GML-026/2. [#21072021]
  • Service difficulty centers on the tuning mechanism: multiple users call the cord refit hard, and one notes that different Amator versions used different cable mechanisms. [#21075125]

What is the difference between the Polish Amator 2B stereo DSS201 and the regular Amator 2, both in features and in the schematic?

The Amator 2B differs from the regular Amator 2 by lacking the tuning indicator. One later correction also says the schematic differs, because the 2B preamp uses only one transistor plus UL1321. That means the change is not cosmetic only; the front panel and part of the audio path differ as well. [#21074258]

How can I find the fuse in an Amator 2B DSS201 and remove the case safely without damaging anything?

The fuse is hidden at the bottom of the case and must be accessed from underneath. 1. Unplug the radio from the mains. 2. Turn the set over and locate the bottom fuse holder. 3. Remove the case carefully after checking that hidden point first. The original post highlights this bottom-mounted fuse specifically to prevent missed fasteners or forced opening. [#21071835]

What are the AM and FM intermediate frequencies in the Amator 2B, and where are they shown in the schematic?

The Amator 2B uses a 465 kHz intermediate frequency for AM and 10.7 MHz for FM. The author states both values directly before introducing the documentation and schematic images, so they belong to the main receiver diagram rather than to a later comment or guess. [#21071835]

What is the UL1321 chip in the Amator 2B, and what role does it play in the audio path?

UL1321 is the dual acoustic preamplifier IC in the Amator 2B. "UL1321 is an audio preamplifier integrated circuit that boosts low-level program signals before the power stage, and in this thread it is identified as a dual acoustic preamplifier used on the radio’s main board." In the 2B discussion, one comment also ties it to a preamp variant using one transistor plus UL1321. [#21071835]

What is the UL1601 in this radio, and how does the stereo decoder work in the Amator series?

UL1601 is the stereo signal decoder used in this radio. "UL1601 is a stereo decoder integrated circuit that separates the multiplex FM stereo signal into left and right audio channels, and the thread lists it as the dedicated decoder block in the Amator documentation." The post shows it as a separate schematic block alongside the main receiver diagram. [#21071835]

What is the UL1211 used for in the Amator 2B, and how does it handle AM/FM intermediate-frequency amplification?

UL1211 handles the intermediate-frequency amplification for both AM and FM in the Amator 2B. "UL1211 is an AM/FM intermediate-frequency amplifier IC that processes the radio’s IF stages, and the thread identifies it as the dedicated AM/FM IF amplifier used in the Amator circuit." Its role matches the stated 465 kHz AM IF and 10.7 MHz FM IF values. [#21071835]

Where did the 2N3055 transistors shown in some GML module schematics come from, and why are they associated with certain GML versions?

They are associated with certain GML versions because some modules used 2N3055 structures inside the ceramic hybrid. One poster says those structures were bought with scarce foreign exchange, while another counters that 2N3055 was also produced by Tungsram and Tesla and later matched domestically by CEMI with BDP620. The key point is that the 2N3055 reference belongs to specific internal GML constructions, not to every module equally. [#21072606]

How do GML-026 and GML-026/2 differ, and which one was actually factory-fitted in some Amator receivers?

GML-026 and GML-026/2 are different circuits, not two names for the same part. A correction in the thread says the linked photo actually showed GML-026/2, and that the presented radio appears to have factory-installed GML-026/2. The same comment adds an edge case: GML-026/2 itself existed in two internal variants. [#21072021]

When replacing a failed output module in an Amator, how do GML-026 and GML-026/2 compare in practical interchangeability?

They are not identical internally, but one commenter says they are functionally identical and can be used interchangeably in practice. That makes them a service substitute, not a schematic match. Use that interchangeability for repair decisions, but keep the earlier warning in mind that the circuits themselves differ. [#21073125]

Why does an old Amator 2 radio only hum after being connected to a speaker, and what should be checked first before assuming major damage?

A hum alone does not prove major damage. One owner reported only hum after connecting a speaker, then immediately noted two likely first checks: the set may still be on the old FM band, and the tuning knob did not have full travel because the dial cord or mechanism had shifted. Check band compatibility and mechanical tuning travel before diagnosing the amplifier. [#21072611]

How do you restring or refit the tuning cord in an Amator 2, and what makes this mechanism so troublesome during repair?

Use the service manual and expect a tedious mechanical job. 1. Verify which Amator version you have, because cable mechanisms differed. 2. Follow the service drawing when routing the cord. 3. Test full knob travel before final assembly. Several users call this job a “nightmare,” and one says the chassis is unfriendly to disassemble during restringing. [#21075125]

What can be used instead of the original tuning cord in an Amator radio, and what are the pros and cons of using monofilament line?

Monofilament line can replace the original tuning cord, and one user says they did exactly that. The advantage is easy availability when the original cord is frayed. The drawback is clear in the same comment: it is a “horrible replacement,” so it works as a practical fix rather than a faithful restoration material. [#21073076]

How hard is it to retune an Amator 2B from the old OIRT FM band to the current FM band, and which stages usually need adjustment?

The thread does not describe a retuning procedure, but it does show why retuning matters: one owner heard only hum and noted the radio was “probably not tuned” because it used the old FM range. In this discussion, the practical first step is to confirm band compatibility before blaming major faults. No specific adjustable stages are named here. [#21072611]

Which spare parts for the Amator 2B are still reasonably available today, including GML modules, Elwa capacitors, and other common failure points?

The thread says spare parts are still obtainable, “even GML-026,” and another comment says Amator transformers remain available at auctions in good quantity and at reasonable prices. Elwa electrolytic capacitors are present in the set and are visually identified, but no supply claim is made for them here. The safest thread-backed answer is that GML modules and donor transformers are still findable. [#21072901]

Amator vs Zodiac or Tosca: how do these Polish receivers compare in serviceability, tuning-cable design, and internal antenna wiring?

In this thread, Zodiac is judged easier than Amator for tuning-cord work, while Tosca is criticized for rougher internal FM antenna wiring. One repairer says the Zodiac was better designed for disassembly. Another praises the Amator when the internal socket-to-UKF-head lead uses real 300 Ω flat antenna cable, unlike the “hackwork” wiring seen in Tosca and, they think, also Zodiac. [#21075125]
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