Kolster k23 radio-AWESOME KOLSTER Underrated
 

Awesome kolster k23 radio. Radios not mentioned much. Push pull output and electrified reproducer.
Each sub chassis has a brass plate with assembly title. Stamped tube designated for sockets. Main chassis. Has quick release for service.
Rutgers univ. Put online a kolster catalog with a wealth of info. Ties to federal and Columbia brands. Lots of photos showing radios being built, industrial installations, research.

I fixed the tuning gang by hand filing down the tight tolerances with the dial drum made of pot metal. There's a rectangle metal guide at the front left of tuning drum that can be dremeled out. I hand filed the dial drum instead. Lots of work. The capacitor gang appears to be made of aluminum and has makers mark.
Way underrated radios. That SAME online catalog states tuning cap cage made out of cast aluminum.
Should be a sweet sound when done.
These sets are seriously worth saving and restoring.

The chassis should be removed when moving cabinet. Heavy radio, two power supplies and heavy cast iron reproducer.

The lower leg cross support trestle is actually made with metal support straps underneath trestle. Still a strain on legs.

My kolster is alive!!!
 

A long ago mechanical problem with tuner drum pot metal piece was trimmed. This I'm sure what made the set non operational years ago 40 to 60 years probaly as couldn'tturn tuner whatsoever... Set was all original with NO REPAIRS.


totally recapped except tune cap blocks on both side of tuner chassis. Was able to get in one station clear but peaking and howling. Will replace all since nearly years old almost and made into a block unit. The sound is great. I'm sure not many of these survived with that weird mechanical defect in an otherwise overengineered radio.

My kolster is fully operational!!!!
 

OMy Kolster fully running now. Sounds great. Those 71a tubes unappreciated. Set has headphone plug and handy phono plug for input. Will post a video of set running when can. 3 chassis beast with speaker! What video format accepted for website?

The dial cord broke! I really enjoyed fiddling with the dial to tune stations. Had small cord perfect for old radio dials. Replaced old bypass caps and st works better now since had tuner chassis out.

The phono input is great for streaming Playlist from my phone for something modern listening when not using AM. It's a shame these sets exist ONLY IN PARTS sets on the web since the butchers don't appreciate these sets. When will they realize no more parts needed for rare radio sets with limited value even when restored?? Is someone finally going to liquidate the dismantled sets so someone can recreate a complete radio????

A separate high impedance headphone jack connects parallel to primary of audio output xfmr. NOT low impence connection!
Definitely high end for its time.

Headphone jack needs high impence
 

So the headphone jack on lower part of set should be high impedance. Of course to match output tube, BUT ALSO audio output transformer primary s not cut out when headphones connected.
A good set with at least 3000 ohms doesn't seem to effect speaker volume. Headset has really good volume.

This may be useful hard of hearing as I had to turn volume quite a bit since loud on phones. An extended cord for phones just thinking of it now will allow distance listening on chair if not another room.

A great added feature not seen on many sets.