sct@lanl-a.UUCP (04/10/84)
Does anyone know what problems and modifications one will encounter
when taking a C-64 computer purchased in the U.S. to England? I know that
the C-64 uses the 60 Hz frequency for timing. What effect will the 50 Hz
power in England have? A step down transformer will be used to get the
voltage down to 120 volts. Can modification kits be pruchased or can
Commodore modify the computer to run properly in the UK? Also, how will the
50 Hz affect the operation of the 1541 disk drive?
Please reply to me at sct@lanl or post. Thanks in advance.
Stephen Tenbrink
Los Alamos National Lab
P.O. box 1663 M/S B255
Los Alamos, NM 87545gear@uiuccsb.UUCP (04/13/84)
#R:lanl-a:-502600:uiuccsb:16800011:000:162 uiuccsb!gear Apr 13 08:54:00 1984 You will also have problems withe the video output as the standard in the UK is different. If somebody knows how to convert a system, I also would like to know.
russell@ihuxu.UUCP (Larry Russell) (04/18/84)
European tv runs 50 Hz vertical and (I think) 300 lines (non-interlaced) horizontal resulting in a 15kHz horizontal oscillator frequency. One would presume that the color-burst frequency would also be different because it is usually some odd number of half-harmonics of the horizontal frequency. To convert from one to the other would seem to be very difficult. It would probably be simplest to take an American monitor with you. Neither the monitor nor the C-64 should care what the power line frequency is, assuming you convert the voltage, because the C-64 derives the 60Hz vertical frequency not from the power line, but by dividing down the 3.58 MHz frequency generated from an internal crystal.
dya@unc-c.UUCP (04/19/84)
References: ihuxu.291
Well, not exactly.... 50 hz, and 15625 hz ( 310 lines )... but all
625 are displayed anyway....
The killer is going to be 1) colour burst frequency and 2) audio
subcarrier frequency. In PAL-B, I think the colour burst is 4.432 mc and
the audio is 5.1 mc.
Actually, the monitor ( if it one of those godawful tv-sets-with-a
-video-input jack * ANOTHER FLAME * ) will care very greatly what the power
line frequency if it uses an SCR time-duration switching regulator. Aside
from the 10hz crawl in the image, the time constants in all this circuitry
will definitely dislike the 50hz line frequency. Most TV sets nowadays use
a mighty strange arrangement for working. For example, RCA uses the charge
of a capacitor through a saturable reactor to just tickle the horizontal
oscillator into operation..this then starts up the entire receiver. Mine says
60 hz only on the back.
Even if your TV set has a real POWER TRANSFORMER, you will still have
to put up with possible 10 hz ripple/bars in the image. I've done the opposite
here ( 625/50 in a 60 hz country ) and even on a $ 6000 Conrac there is some
of this effect ( presumably due to modulation of the HV supply ).
David "Hi-Fi video that you've been reading about is a FARCE" Anthony
( decvax,akgua,philabs ! mcnc !urp!dya )