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Year: 1960–1962 | Category: Broadcast Receiver - or past WW2 Tuner | ||||
Valves / Tubes | 9: ECC85 ECH81 EF89 EF89 EM84 EABC80 ECC83 ECL86 ECL86 | ||||
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Semiconductors (the count is only for transistors) | B250C150 OA180 |
Main principle | Superheterodyne (common); ZF/IF 460/10700 kHz |
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Tuned circuits | 6 AM circuit(s) 12 FM circuit(s) |
Wave bands | Broadcast, Long Wave, Short Wave plus FM or UHF. |
Details | |
Power type and voltage | Alternating Current supply (AC) / 110, 125, 220, 240 Volt |
Loudspeaker | 4 Loudspeakers |
Power out | |
from Radiomuseum.org | Model: Concertino 2194 [poliert] - Telefunken Deutschland TFK, |
Material | Wooden case |
Shape | Tablemodel with Push Buttons. |
Dimensions (WHD) | 640 x 375 x 270 mm / 25.2 x 14.8 x 10.6 inch |
Notes | Stereo-NF-Verstärker, 7-W-Gegentakt-Endstufe in Zweiwegtechnik. Parallelgerät zum AEG Tambour 61. |
Net weight (2.2 lb = 1 kg) | 14.3 kg / 31 lb 8 oz (31.498 lb) |
Price in first year of sale | 459.00 DM |
External source of data | Erb |
Source of data | HdB d.Rdf-& Ferns-GrH 1961/62 |
Literature/Schematics (1) | -- Original-techn. papers. |
All listed radios etc. from Telefunken Deutschland (TFK), (Gesellschaft für drahtlose Telegraphie Telefunken mbH
Here you find 3461 models, 3030 with images and 2006 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
Hits: 1530 Replies: 3
telefunken: 2194; Concertino. AM IF Frequency ?
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Howard Craven
04.Feb.14 |
1
Hello, I have just overhauled a 1961 Telefunken Concertino 2194 and I have a question about its AM IF frequency. It's currently set to around 480kHz, some way off the 460kHz stated in the service manual but I don't think the set has been tampered with. Stamped on one of the IF transformers is '485kHz', which may suggest that for the UK and other export markets it was changed. Is it likely that the AM IF frequency on exported versions of this set would be set to 485kHz? I have overhauled several German built radios of this era and the AM IF frequency has always been the same as the German market sets. If so I shall align it to 485kHz as it has drifted and the set is lacking a little gain on all AM bands. Regards ............ Howard Surrey Hills, England
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Hans M. Knoll
04.Feb.14 |
2
Hello Howard. If your radio is made for the market in Luxembourg or France, certain the 485Khz realistic. Why?
The Station Luxembourg make an interference (*) of his own reception frequency = 234 khz, e.g. 2x 234Khz = 468khz - 460 Khz = 8khz. interference, this is audible. SABA built models for LUX. with 479 Khz as IF. What means an interference = 11Khz. With your IF of 485 Khz, are the difference = 17Khz. GRUNDIG an Philips use for BENELUX= 452khz. That makes 468- 452 = 16 Khz All this are far or outside of the audio Range from the IF -Channel mfg Knoll
(*) nonlinearity of the Mixer-Tube Attachments
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Howard Craven
05.Feb.14 |
3
Hello Hans, Thank you for your reply. I don't know the history of this Concertino but it does not have a UK dial nor English lettering so may well have been built for the Luxembourg market. I will therefore align the AM IF to a frequency of 485kHz as it has obviously drifted and hopefully the set will then work better than it does now. Regards ...... Howard
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Michael Watterson
06.Feb.14 |
4
Now 472KHz to 480KHz is allowed in many European countries for Amateur 1W EIRP, which could be a 2kW power amplifier. So 485kHz or higher (or 467kHz and lower) is better than 480KHz, assuming a +/- 4.5KHz bandwidth. However like the 137kHz Amateur use it's not likely to be too common. |
Hits: 4059 Replies: 3
telefunken: 2194; Concertino - Audio circuit questions
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James MacWilliams
12.Apr.10 |
1
This model has a stereo audio circuit. From studying the schematic, it seems to have an extra triode in the left channel. After the volume control, the audio signal for each channel goes through through a triode. In the case of the left channel, that triode is part of the EABC80 and in the case of the right channel the triode is part of the ECL86. The output of the right channel triode goes directly to the pentode section of the ECL86. The left channel, however, goes through the triode section of the ECL86 before it is applied to the pentode section. I have two questions concerning this model.
Best Regards, Jim |
Günther Stabe † 19.8.20
13.Apr.10 |
2
The extra tube is a phase inverting stage because the deep frequencies below 300 Hertz run on the push-pull stage with a special coupling transformer. The higher audio frequencies will use the smaller transformers as two single amplifiers, but the polarity is vice versa depending on the changed phase. This application had been described in depth in the electronic magazine FUNKSCHAU in 1957/1958. Some years ago I took some copies of this article but today I didn't find it within my other paperwork. My guess is - I shreddered the copies with other material.... Perhaps another RMOrg member owns this magazine and is able to transmit the original - or a translated version - to you. The trim potentiometer is an adjustment for the phase inverter; the 18 kOhm resistor leading to the plate must be also with the same value - depending on tolerances - as the summary of the cathode resistor(s) 1.2 kOhm and the adjusted value of the trim pot. Only when both Ohm values are equal the phase inverter will work well resp. as designed. G.S. |
James MacWilliams
13.Apr.10 |
3
Thanks for that. I would like to see the article you refer to. German would be fine as I can have it translated. So I assume then that with the cathode resistance matching the anode resistance the gain of this stage would be -1? I'll check this on my 2194. Certainly an interesting design. |
Günther Stabe † 19.8.20
13.Apr.10 |
4
You are absolutely right: no gain, only inverting for the push-pull function. G.S. |
Hits: 4217 Replies: 15
telefunken: 2194; Concertino -- UKW not working
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James MacWilliams
07.Jul.09 |
1
I am restoring a Telefunken Concertino 2194. I have replaced all the paper capacitors and a couple of resistors that were out of tolerance. The radio works well on all the AM bands - LW, MW, and KW -- and sounds great. FM (or UKW), however, is not working. It does receive one station, extremely weak, volume has to be at maximum to hear it. This station is just outside the FM band the radio should receive -- 101.0 MHz. All the voltages are okay. I have checked the waveband keyboard switches and they are okay. I have tried known good tubes (valves) -- ECC85, EF89 (2x), ECH81, and EABC80 with no change. I have made some DC resistance checks through the FM front end section with the ECC85 removed to verify the resistors. They are okay with the exception of W604 which should be 33k and I measure 21k. But I am not sure how to open the front end section, so nothing has been changed (or cleaned for that matter). I am hoping for some suggestions on where to procede. Or perhaps notes on how to open and service the FM front end. Has anyone had similar problems with this model? Any guidance would be appreciated. Regards, Jim |
Hans M. Knoll
08.Jul.09 |
2
Hello Jim. If you want,read here. Maybe a solution for parts of your problem. post # 4,8,10,12,14,16, and 18. 8 is important.
hans m. knoll
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James MacWilliams
08.Jul.09 |
3
Thanks Hans. That link will be a big help. First, I now know how to open the RF section. Second, it gives lots of help in understanding how it works and what is important. Much appreciated. Jim |
Hans M. Knoll
08.Jul.09 |
4
Hello Jim
Important is: the cores inside the FM-Box being moved via Dial? Post 8, Local Osc. works ? Without this, no reception is doing. Your Signal at 101 can bee something e.g. Overloading the RF- Stage. hans |
James MacWilliams
08.Jul.09 |
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Hi Hans, With the information in the thread you provided I was able to remove and open the FM front end. The good news: the cores are okay and moving properly. So far I have been able to only inspect the unit. Everything looks okay. I did test the diode. It is okay. The resistor I was concerned about is really a 22k resistor. The schematic shows a 33k resistor there. Perhaps this resistor (W604, the bias resistor for the anode of the oscillator) is selected during manufacturing. Based on your explanation in the other thread, I suspect the oscillator is not working and the radio station I hear is due to the mixing of two stations. The schematic shows that both the RF amplifier and the oscillator should draw 12.7 mA. I will verify that. The schematic also shows a switch S7 that is part of the FM tuning knob. What is the function of this? Jim |
James MacWilliams
08.Jul.09 |
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Hans, I read further in the other thread and now realize that S7 must be part of the AFC circuit. But I'm still uncertain what it does? |
Hans M. Knoll
08.Jul.09 |
7
Hello Jim. You must go to post 8 an realise the Measuments DC- Volt on Testpoint on FM-Box or this test
If you not understand what's do to? Let me now. It's abolute important. hans Attachments
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James MacWilliams
09.Jul.09 |
8
I will try these tests this evening. Thanks for the help. Jim |
James MacWilliams
09.Jul.09 |
9
Hans, I performed the test you requested. At the test point I measure -3.3 vdc. Looking at the signal on the test point with an oscilloscope, I see a sine wave from 0.0 vdc to -5.6 vdc at 11.02 MHz. I think this is okay? Any thoughts? Jim |
Hans M. Knoll
09.Jul.09 |
10
Hello Jim.
I will say, nothing is allright.
There is not any reason for 10 + / - Mcs on testpoint
If that is right, oscillate the stage (mixer_osc) on IF = 10,7 Mcs not aproxx 100Mcs.
Also then you can measures, negative voltage by the Test point, it works like a BC (MW_LW) Osc. together with the IF-Coils
Three ideas.
Solder 150 to 220 pF in parallel to C616 130 pF
Or, an 3300 to 3900 pF in parallel to C610 3300 pF
Or break Resistor W602 on one end. This stops RF- Stage. Maybe she oscillate on RF Frequency and overload the Mixer_Osc.
And repeat the measurments again, each.
See Diagram
![]() Hans
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James MacWilliams
09.Jul.09 |
11
Per your request, here is what I measured:
All of these tests were done with the RF box removed from the chassis. RF box assembly is open. Jumper wires are used to connect HT (170 vdc), 6.3 vac, and earth (ground). Any suggestions? Regards, Jim |
Hans M. Knoll
09.Jul.09 |
12
Hello Jim.
Everything it is possible how I mean.
If the oscillator does not oscillate on 100Mhz, the conductance of Tube is 5 to 6 times larger and the tube see here on page 4
The additional condenser parallel to the 130pF, stops Regeneration on 10.7 Mhz.
Now, one off the Ceramics around the Mixer-Osc. Tube is wrong. I can not see who !
I don’t now, if you can read german. There was the same problem.
This engineers well informed, have no solutions for here Problem.
Tomorrow I can give you a paper on Rmorg. What ceramics take part.
My job was to show that local-osc. ist out of function!
That’s all I can do for you
Hans
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James MacWilliams
10.Jul.09 |
13
Hans, I appreciate all the help you have given. I will also check the sources you supplied. Many thanks. Jim |
James MacWilliams
10.Jul.09 |
14
Hans, I suspect the 11 MHz oscillation may be due to the oscilloscope (O-scope) probe. I put the assembly back in the box for proper shielding. I also mounted the box back on the chassis to provide a proper ground (earth). I connected HT and 6.3 vac. I then measured the voltage at the test point through a 100K ohm resistor using a DC voltmeter (per other thread). I measured -2.95 vdc. Still using the 100K resistor, I measure the same with the O-scope with no oscillation. But without the 100K resistor and probe directly on the test point, it oscillates at 11 MHz. Still, I do not see any oscillations on this test point in the 100 MHz range. I am tempted to re-connect all wires to see if anything has changed. Regards, Jim |
Hans M. Knoll
10.Jul.09 |
15
Hello Jim. As an installation you can find a picture with components. What i think is: the Diode ist wrong! O.K. you think no!
EDIT: More. Uses Portable radio, tune the VHF box on lower end (88 Mcs) Bring the rod antenna of the portable near to the ECC85 bulb and search at 88 + 10,7= 98,7 for a strong carrier. If an local VHF Carrier is busy there. Move the Box a little bit higher. Switch the VHF- Box off and on to test what Carrier you receive. Booth, that and use off VTM and 1 Meg. i have recommendet long bevor.( post 7, above) I am sorry, english ist not my language! I wish you a lot of success . Hans |
James MacWilliams
15.Jul.09 |
16
Hans, I have determined the faulty component, C616 - 130 pF capacitor. I did a number of things to simplify the circuit.
I still have to undo the other modifications I did, but I feel certain it will continue to work. Thanks for all of your suggestions, you have been most helpful, and I would not have gotten there without your assistance. Regards, Jim |