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-   -   Bell & Howell 8D-655, amplifier question (https://www.vintage-radio.net/forum/showthread.php?t=185207)

TwelveAxSeven 27th Oct 2021 3:45 pm

Bell & Howell 8D-655, amplifier question
 
Hello all,

I am looking for info on the Bell & Howell 8D-655, which I understand was the model that preceded the 655 TQ1 series, or 655Q. Not quite sure.

I think the 8D-655 had a decent valve amplifier that can be reused, while the TQ1 was solid-state.

Does anyone have any insight please?

wd40addict 27th Oct 2021 4:29 pm

Re: Bell & Howell 8D-655, amplifier question
 
The 8D prefix marks when production of the Anglicised projectors moved from the UK to Japan. I have the 8D644 which is based on the 644, the amplifier is still valve based but has been changed to use a solid state doubler rather than an EZ81 for HT rectification and a transistor has been added as an extra preamp stage for the optical sound.

The following TQ1 series used a low voltage lamp for greater screen illumination and all transistor anplifiers.

TwelveAxSeven 27th Oct 2021 6:57 pm

Re: Bell & Howell 8D-655, amplifier question
 
@wd40addict: Great to know thank you


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