Replacement RA Motor Encoder for LX200GPS

[turbo_pascale (Rob)]

I've been able to determine that the encoder on my RA motor from my LX200GPS is not working. This is the result of my "Motor Stalled" message on startup.

The motor itself works, but there is no output from the encoder.

The encoder is a US Digital E4-256-091-L, which is a discontinued product. Their replacement product (E4T) does not come in a configuration with the same bore diameter, so is not a drop in replacement.

I'm specifically looking for either someone who has a spare motor (either RA or DEC motor) from an 8", 10" or 12" LX200GPS, or someone who has a burnt out motor from one of the above which I could salvage the encoder from.

In the interim, I'm trying to see if US Digital can offer a replacement that could work, but hoping it's easier to see if someone else has some parts in a back room stash somewhere that is for sale.

Thanks.
Turbo

[bojan]

Is it similar to this one?
I think Allegro or HP has encoder modules used in this product.

I think I posted details on my project with those encoder modules some time ago, I wil check


EDIT:
have a look here, post #7:
http://www.iceinspace.com.au/forum/s...ective+encoder

[turbo_pascale (Rob)]

The spec sheet you link to is the correct one - but I heard back from US Digital - they literally have no legacy stock of the original encoder anymore.

US Digital E4-256-091-L

256 CPR, 091/2.3mm bore, Low Power Strobe

I've managed to get a motor (arrives monday I hope - Thanks Don @ BinTel for digging through the vintage gear!), but I am still keen to see if I can find an encoder solution for the future. If no one makes something suitable, it's going to be hard to repair these scopes in the future, which is just disappointing.

[bojan]

I think your encoder may be designed around this or this module.
If yours is defective it can be replaced with above..


another link for possible replacement:
https://www.robotshop.com/en/miniatu...e-encoder.html



Alternative is replacement of the whole system with OnStep or similar.

The cost is not prohibitive, it is based on Arduino h/w and steppers are also cheap.. but it involves DIY, so it's not for everyone.