5 replies to this topic

[John Jarosz]

In the 60's and 70's Criterion used to advertise a gizmo to vary the speed of their synchronos drive (electrically). They sold it for $90 or so which seemed cheap compared to the cost of the scope. I assume it's something that varies the electrical frequency. Is there a source for something like this? Or some contemporary equivalent? I've not seen anything like this crop up on the auction sites.

Thanks

John

[jrcrilly]

I don't know of any new drive correctors that are currently available but the Meade #43 pops up from time to time as new old stock. This outfit always seems to have some.

[John Jarosz]

Thanks John,
Is that 12VDC input and 110AC output? I have seen those before but I always thought it was DC output for a DC motor.

There is very little info on old Meade stuff on the web. I'm surprised what I can't find with Google here.

john

[Mark Lancaster]

The variable speed drives rectified 120 VAC to 12 VDC, then converted back to 120 VAC with a frequency range typically spanning 50-70 Hertz, or greater. These units also accepted 12 VDC directly for use in the field.

They often show up on Astromart. These three appeared last month:

http://www.astromart...ified_id=459194

http://www.astromart...ified_id=459164

http://www.astromart...ified_id=458307

[John Jarosz]

Thanks mark, exactly what I was thinking of. Now I know what I'm looking at.

john

[tybee]

The Meade #43 was a basic drive corrector which ran on 12VDC only. The JMI Mototrack V was about the ultimate which even had provisions for PEC, CCD autoguider input and DEC control. I've owned and used both.