AZEQ6 Fail - Reverse polarity

[Cliff]

Hi all,

New here, having just got this AZEQ6 used, I inadvertently reversed the power, has taken out both the handset and controller board.

I've fixed the handset, but looking for anyone with information or schematic on the Synta MC007 board that is in the mount.

Below are the suspect parts thinking they are 3.3V and 5V regulators, it was a 3.3V in the handset that went.

Thanks in advance
Cliff

[Lady Fraktor]

Good luck, hopefully you can get it figured out.

[Cliff]

Thanks I've decided to upgrade it to the latest USB/Wifi board SW make a kit for it.

[Cliff]

Though would be nice to fix it as a spare.

[yobbo89]

11 17 voltage regulator and other looks like says 11 - 50?

https://m.alibaba.com/product/604497912 ... 33-17.html

[yobbo89]

Don't these things have polarity protect??

[Cliff]

No reverse polarity protect not even on Tak mounts I believe this is crazy on expensive gear.

Might think about putting a DC-DC converter inline will protect from reverse and also provide a constant voltage and settable current limit.

[Cliff]

11 17 voltage regulator and other looks like says 11 - 50?

https://m.alibaba.com/product/604497912 ... 33-17.html

Yep thats what I think I replaced the one in the handset with a AMS 1117-33 works perfect but the original ended with N 50 just to be confusing

suspect similar in the controller but think U9 is 5V and U10 is 3.3V , I have plenty of the 3.3V and waiting on the 5V one. Worth a try anyway.

[yobbo89]

Good idea, that's ridiculous not having reverse polarity protection, dose the chip atleast have a fuse lol

[yobbo89]

11 17 voltage regulator and other looks like says 11 - 50?

https://m.alibaba.com/product/604497912 ... 33-17.html

Yep thats what I think I replaced the one in the handset with a AMS 1117-33 works perfect but the original ended with N 50 just to be confusing

suspect similar in the controller but think U9 is 5V and U10 is 3.3V , I have plenty of the 3.3V and waiting on the 5V one. Worth a try anyway.

I think you're right on those number, last digits are the voltages 33 for 3.3 v and 50 for 5.5v and i think the 17 is the type for the pin out

[KathyNS]

No reverse polarity protect not even on Tak mounts I believe this is crazy on expensive gear.

Since you are comfortable going into the innards, why not wire in your own reverse polarity protection. A power diode in series with the power input would do the job.

I agree it's crazy, on a piece of gear that costs $2000, to leave out a 25-cent component that would protect it.

[Cliff]

Only problem putting a fuse in line is the 0.6V or so voltage drop not a big deal on a 13.8V power supply but not good on a 12V battery.

The cable did have a 5A fuse not sure thats even right as this mount was bought used ,but that was next to useless, it did blow but after the damage was done. No fuse in the actual mount though

I'm also a Ham Radio Operator and everything is well fused and generally protected, from my short time in Astronomy it seems the electronic design takes a back seat to the mechanical side.

Yes I was a avionics tech for an airline for a long time. So I know a little about electronics though getting rusty in retirement.

Appreciate all the replies, have ordered the replacement upgrade board but will continue and try and fix the original .

Cliff

[Cliff]

Only problem putting a fuse in line is the 0.6V or so voltage drop not a big deal on a 13.8V power supply but not good on a 12V battery.

The cable did have a 5A fuse not sure thats even right as this mount was bought used ,but that was next to useless, it did blow but after the damage was done. No fuse in the actual mount though

I'm also a Ham Radio Operator and everything is well fused and generally protected, from my short time in Astronomy it seems the electronic design takes a back seat to the mechanical side.

Yes I was a avionics tech for an airline for a long time. So I know a little about electronics though getting rusty in retirement.

Appreciate all the replies, have ordered the replacement upgrade board but will continue and try and fix the original .

Cliff

First line should've read Only problem putting a DIODE in line is the 0.6V or so voltage drop

[KathyNS]

Only problem putting a fuse [diode] in line is the 0.6V or so voltage drop not a big deal on a 13.8V power supply but not good on a 12V battery.

Except that a battery in good condition should be well over 12 volts. If it's down to 12 volts, it's almost dead.

[Cliff]

Yes about 12.6 -13V at full charge on my Gellcells so might be ok.

[Cliff]

Found out today the new AZEQ6 GT does not have Wifi only USB many sites showing it has Wifi but I was just informed by a local astro shop who talked with the supplier here in Sydney and it does not have Wifi built in.

Looks like back to using my Stellermate device.

[Cliff]

Well not quite fixed but I did get a new board for the mount and replaced it, having also found some wiring errors associated with the switch and power, the actual power lead was wired incorrectly as well .

If it doesn't rain it pours, anyway checked it all out on a Lab 12V current limited supply and the board worked fine.

So reassembled it into the mount and all seems to work as it should , Now to learn the differences in operating from my iOptron handset for the Minitower and the repaired Synscan one. I miss the built in GPS in my iOptron Minitower Pro.

Certainly a lot quieter in slewing.

Still waiting on parts to fix the old board.

I got rid of the horrible Cigarette lighter plug and fitted Anderson Powerpoles my preferred DC connector.

[Cliff]

While hunting around the net and looking for something without the 0.6V diode voltage drop I came across the idea of using a P-chanel power mosfet. A Schottky diode is another option but it has about .3V drop.

The Mosfet has Virtually no voltage drop and little power dissipation. Should be incorporated in all the expensive gear.

I attached a pdf showing how it works.

[Cliff]

Well looks like the original Motor board is working ok again, had to replace Both U9, U10 5.5V and 3.3V regulators.

Good as a spare (hope I never need it though)