The Nordmende Phonosuper radio that I restored recently (see link to playlist below) came with an unusual 'appendage' at the back which I failed to identify at first.
It turned out to be an amplifier module that is quite interesting. It was used in the Decca RP 205 record player from 1964, and was obviously added here to give the radio's phono function a stereo output.
It uses an ELL80 output tube, which is a dual pentode in one package, making the construction of a push-pull stage quite simple, albeit at low power.
The restoration of this little amp was fun, and the result, while quite useless for any hifi use, is perfect when used as a guitar amp.
Enjoy.
See a series of 'Restoration Building Blocks' videos on detailed steps in the restoration process:
https://www.youtube.com/watch?v=7xvTGd4ysRE&list=PLy5M_tA9ux7JSYx8z2mw303vx287LHpzf
See also playlists on some other completed restoration projects.
NORDMENDE PHONOSUPER:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7JgKx-BZHNSEMl6trb5-BhH
PHILIPS BX750A:
https://www.youtube.com/watch?v=i8U9Lteja5o&list=PLy5M_tA9ux7IG6XgctidGO0u0DeT3_CxF
TELEFUNKEN OPUS 2114:
https://www.youtube.com/watch?v=_HO2bjY5vuw&list=PLy5M_tA9ux7LhcZ9h9plfTFmjaM1mcifu
SABA UW-175-Z 3D:
https://www.youtube.com/watch?v=cca4i60ZLw4&list=PLy5M_tA9ux7IWL18nsrSf4RnjsuPjHC-p
GRUNDIG 1070:
https://www.youtube.com/watch?v=i4J5l0fwhko&list=PLy5M_tA9ux7JgnyYPRWOK763aJ8bg3iCI
SCHAUB-LORENZ GOLDY 58 type 3020:
https://www.youtube.com/watch?v=RSbt7qVed78&list=PLy5M_tA9ux7IBse5G--Kl89SPS9sATXfZ
BUSH VHF64:
https://www.youtube.com/watch?v=U--6JymkQ1M&list=PLy5M_tA9ux7KsvN5M48cX6cxN4jSz0s3X
GRUNDIG 3060A:
https://www.youtube.com/watch?v=7x2sK2GSYeE&list=PLy5M_tA9ux7L8e9h8lrHGREPqcgWO-YQm
TELEFUNKEN OPERETTE 8:
https://www.youtube.com/watch?v=5IsACM0mPzs&list=PLy5M_tA9ux7K3SXDv8Hu4uAyl1O7NE5dc
GRAETZ SUPER 171W:
https://www.youtube.com/watch?v=MhG-CH0gqm4&list=PLy5M_tA9ux7IjUykGE8neJSI6GUxMl2YG
LOEWE-OPTA MAGNET 3737W:
https://www.youtube.com/watch?v=ZSZBJ5sKQm8&list=PLy5M_tA9ux7J_hzDhnF8rs2c7wmgGfRlK
BRAUN ATELIER 3:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7L3k5nPRvrk1aH764QRCTqE
LOEWE-OPTA TRUXA STEREO 4741W:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7KhVk0KqPx0Wkh2KO_5f2fQ
GRAETZ COMEDIA 616:
https://www.youtube.com/watch?v=fwmW9k3TwNE&list=PLy5M_tA9ux7L5sAApLzV6xoYzmRNJpMW5
SABA FREIBURG W2:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7IqvS-LshUGpE1D_WY6mrZe
GRAETZ MUSICA 4R417:
https://www.youtube.com/playlist?list=PLy5M_tA9ux7Ios98E59dWjwc2SRJyxwIn
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CAPACITOR LEAKAGE TESTER:
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