OUCH ! , I looked at Mike Weasners page , a lot to take in .
Are you saying the 497 will run the ETX70? with the #506 cable ?
Thanks mate.
Brian.
Quote:
Originally Posted by Barrykgerdes
Hi Brian
I bought an ETX 70 a few years ago to find out how to fix some of the problems.
1. Repairing the focus control when it runs off the end of its control.
2. The stability of the simple tripod. This was the cause of the telescope often falling over and wrecking the focus and plastic drive components.
3. How to drive a 494 controller from Stellarium
See Mike Weasner's pages on the ETX60/70/80
The ETX worked pretty much as expected out of the box but the 494 controller is a bit of a dog to use. However I managed a shot of the moon with an LPI.
To connect to a computer it needs a special cable #506 that converts the RS232 to TTL for the utility socket on the base.
I modified the battery box to take an external power supply because I intended to run it for long periods connected to a computer while we wrote the interface to Stellarium
Eventually the AZM drive started to get jumpy. I managed to get it apart with great difficulty and found that the plastic AZM drive was broken rendering it forever useless. This I have since found is a fairly common problem. I made partial repairs and got the unit working for a couple of days but it soon broke again.
Since then I have come into possession of a couple of early old type DS2114 type mounts with broken Altitude bearings and faulty 494 controllers. I remade the bearings successfully. I do have an extensive workshop. I then salvaged th ETX70 OTA and cut the pivots off and cleaned up the tube. I then made a bracket to attach the OTA to the mount.
It works perfectly now. I also modified the battery carrier for external power. They need 12 volts rather than 9 volts else you will regularly get the motor fault indication when slewing.
I next purchased a 497 controller (Bintel Sell Them) which is quite compatable with the mount and connects to the computer with the #505 cable OK.
I now have a nice little goto telescope. Any offers?
Barry
PS I still have the parts (the undamaged one) from the old ETX70 mount. Also check the cable numbers from the Meade web site. I may have got them wrong.
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