What switch to use for gfx-card and scandoubler?

[Jettah]

Hi,

My son came asross a boxfull of old games on floppies.

They can only be played through the old, scandoubled, video system.
All right the scandoubler is there and functioning and I use a CV64/3d card. But a mechanical switchbox, which houses a birdsnest of wires, and two extra video cables deteriorate the video signal quality quite severely.

What switch can you recommend that has no visible impact on the quality of the video signal?

(Current system: A1200 in ElBox tower, Blizzard 040 + SCSI, Apollo ZIV-board + CV64/3d (+ however irrelevant: X-Surf, ISDN & HyperCom Z4))

Thanks,

Tjitte