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TonyDuell · 9th Aug 2017, 5:10 am

I wrote several of the messages in that thread...

The N4418 is similar to the N4510 but has power amplifiers and speakers built-in. The N4510 is line level and headphone output only. Both are 3 motor, 3 head machines, only run the tape left-to-right and have 6 flip-flops (2 boards of 3 each).

The N4450 is the big one, takes 10.5" spools. It has power amplifiers (but no built-in speakers). 3 motors, 6 heads. Runs the tape both ways with autoreverse. 8 flip-flops.

There's a monostable multivibrator in the autoreverse circuit of the N4450 that uses an NPN and a PNP transistor, although both are silicon (BC147 and BC157 originally).

9th Aug 2017, 5:10 am	#37
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,208	Re: Philips N4450 I wrote several of the messages in that thread... The N4418 is similar to the N4510 but has power amplifiers and speakers built-in. The N4510 is line level and headphone output only. Both are 3 motor, 3 head machines, only run the tape left-to-right and have 6 flip-flops (2 boards of 3 each). The N4450 is the big one, takes 10.5" spools. It has power amplifiers (but no built-in speakers). 3 motors, 6 heads. Runs the tape both ways with autoreverse. 8 flip-flops. There's a monostable multivibrator in the autoreverse circuit of the N4450 that uses an NPN and a PNP transistor, although both are silicon (BC147 and BC157 originally).