NEWSLETTER APRIL 2002

We have succeded in getting more power from the motors. The price list shows 24V supply items now. Working at the higher voltage does get the current into the coils faster so the stepper motors can now work at higher speed for the same output power. You can now purchase a power supply and a Microstep drive box based on 24V. An additional item is a fan assisted resistor dropper box which is essential for dissipating the extra power.

A new range of motors by Sanyo-Denki has been evaluated and these produce a smoother ride with higher power outputs than the previous motors. These are now fitted to all Microstep systems. They use rare-earth magnet technology and offer about 20% more power for the same size unit with the same drive current.

The FRGEN has been improved by the provision of a constant current chopper design working with internally generated 27V supply. Some motors stall at a lowish speed becasue of phase current modulation (at mechanical resonance) and the chopper design gets over this. The existing bi-level design has proved itself as having substantially the same performance as this on some motors that we supply, so either design could be supplied.

Newly released version 0.59 software incorporates BACKLASH COMPENSATION. Once this has been programmed it works even with operation by Simple Handset, so all users would benefit from an upgrade. No matter how good the drive reduction is, there is always going to be some backlash, even if it is just compensation for the angle needed by the motor to supply the output power.

BACKLASH Compensation, programming and coordinate correction, data entered in arc seconds. AWR mode of HOST communication which offers 1 arc second coordinate resolution. Extra information from the IDS to the HOST. Bigger command buffer between the IH and the Drive Box to reduce instances of "USTEP COMMS ERROR". Extra timeouts to avoid a blank display at power up which some users have experienced.

We are currently shipping software versions V1.3 (IH), V0.59 (Microstep and FRGEN).
Software upgrades are available free of charge to existing customers. There will be a small charge (for postage) if you return goods for us to fit the upgrades.

On the website there is now a dedicated page for IDS OWNERS at http://www.awrtech.co.uk/ih/

• INTES-MICRO ALTER D6 - Achieves 0.6 degrees per second with new motors and Microstep box.
• MEADE LX50 Maksutov - Added DEC worm wheel and two STEP5 motors with FRGEN drive box achieves 0.6 degrees per second slew.
• MEADE STARFINDER 16 INCH - Added worm wheel sets and brackets on both axes with high power MOTOR/220 reaching 0.5 degree per second slew.

If you wish to see products before purchase then it is possible to view at our premises by appointment, please phone first. There is normally some equipment being built to show.