Stereo-Konzertschrank KS620 Ch= HF45

Grundig (Radio-Vertrieb, RVF, Radiowerke)

  • Year
  • 1965/1966
  • Category
  • Broadcast Receiver - or past WW2 Tuner
  • Radiomuseum.org ID
  • 26161
    • alternative name: Grundig Portugal || Grundig USA / Lextronix

Click on the schematic thumbnail to request the schematic as a free document.

 Technical Specifications

  • Number of Tubes
  • 7
  • Number of Transistors
  • Main principle
  • Superheterodyne (common)
  • Tuned circuits
  • 6 AM circuit(s)     10 FM circuit(s)
  • Wave bands
  • Broadcast, Long Wave, Short Wave plus FM or UHF.
  • Details
  • Changer (Record changer)
  • Power type and voltage
  • Alternating Current supply (AC) / 110; 130; 220; 240 Volt
  • Loudspeaker
  • 2 Loudspeakers
  • Material
  • Wooden case
  • from Radiomuseum.org
  • Model: Stereo-Konzertschrank KS620 Ch= HF45 - Grundig Radio-Vertrieb, RVF,
  • Shape
  • Console with Push Buttons.
  • Dimensions (WHD)
  • 1180 x 800 x 370 mm / 46.5 x 31.5 x 14.6 inch
  • Net weight (2.2 lb = 1 kg)
  • 42 kg / 92 lb 8.2 oz (92.511 lb)
  • External source of data
  • erb

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The model Stereo-Konzertschrank is part of the collections of the following members.

 Forum

Forum contributions about this model: Grundig Radio-: Stereo-Konzertschrank KS620 Ch= HF45

Threads: 3 | Posts: 15

After using my perfectly rehabbed unit for a few months, I noticed that sometimes the stereo signal was off and the output was in mono.  I would turn off the stereo, turn it back on and most times it would start working in stereo again.

However, after a few more weeks, this was no longer working to get the output to be in stereo.  Now, when the tubes are warming up, I can hear it trying to put out a stereo signal (the stereo light is lit), but after about 10 seconds, the stereo light goes dark and a mono output comes through loud and clear.

I'm looking for some directions on what could be wrong before I take everything apart in a few weeks when I have the stereo moved back home.

Thanks in advance for any guidance!

craig.

Craig Vodnik, 22.Sep.13

Weitere Posts (7) zu diesem Thema.

I'm trying to calculate some voltages from the schematics in order to test my capacitor replacements.  On the schematics, the three capacitor group C83, C86 and C88 are all electrolytic caps.  C88 has a 285V value, but I want to calculate C86 and C83 for testing purposes.

It may not be this easy, but C86 looks like it should have a 1000 Ohm * 0.98 Amp = 98 Volt drop from C88, resulting in a value of 187V.  Is that too simplistic because there are other things going on in the circuit?  And how would one calculate the voltage at C83 since there isn't a clear one-to-one calculation like for C86?

And how long after turning on a console such as this should I wait for the voltage to stabilize to accurate readings?  I'm guessing 10-15 seconds based upon how long the sound takes to start up.

Thanks for any guidance!

craig.

Craig Vodnik, 01.Jan.13

Weitere Posts (2) zu diesem Thema.

I recently bought a working KS620U that had trouble tuning past a certain point of the FM dial.  So I took the chassis out and used deoxit to try and loosen the tuning knobs and wheels.  Unfortunately, the string that transfers the knob turn to a new freqency on the radio snapped  (it was difficult to turn).  Here's a picture of the snapped string:

 

Does anyone know where to get replacement string like this?  I bought a nylon guitar string to try, but it doesn't seem to have enough friction when around the tuning dial.

Thanks in advance!

craig.

 

Craig Vodnik, 25.Nov.12

Weitere Posts (6) zu diesem Thema.