Sxv-ao lf

[multiweb]

Finally got this AO working after many emails back and forth so here it is all laid out on the table:

1_ This AO is very unlikely to work from a laptop. PC no problem. Laptop big problem.

2_ You'll have to update the firmware to the latest version 20. Mine was delivered with version 18.

3_ A quatech USB Serial adapter is best. They're pricy but they work and can be purchased in Oz for approx $130.00 inc delivery.

The problem with the AO is that it needs +5V supplied to pin3 to work correctly. A standard DB9 serial PC port will supply that. A USB Serial adapter will not. As a result you will transmit commands to the AO but you won't get any feedback. There is a program called PORTMON from the microsoft website that will sniff any COM traffic and that's very handy to diagnose connection problems.

So here's the fix: Go to JayCar, buy a 2.2k Resistor and a small phone RJ12 Female box. Will post a picture later. Because they only come with 4 pins you'll have to hack another one to re-insert #6 & #1 in there. Also get a small DIN power plug.


Then you need to soldier pin3 to the resistor then soldier the resistor to the + of your power source (6V), then soldier the - of your power source to the ground pin #5. The rest of the pins just go through.

So in order you have AO Serial Output RJ11 M -> to Box -> AO cable (RJ12 toDB9) -> Quatech USB to serial -> USB port on laptop.

When running the AO feed the box 6v that will set +5V on the hot pin. Then everything will work fine, including MAXIN DL 5.11 as the AO cycles and doesn't time out any more.

HTH. :thumbsup:

[taxman]

Wow.

I might have to change my combined Christmas/birthday/long service payout gift request until this gets sorted out...

:eyepop:

[multiweb]

Just got told that apparently the pull-up is now done internally in the latest batch so only the original roll-out is affected. Sounds like a few people had troubles with USB serial adapters.

[gbeal]

Finally. Shame you had to do all the graft though. Don't seem right somehow.
Gary

[multiweb]

Got peed off at first but I'm ok now :) That'll teach me to buy the latest stuff. ;) Got to admit the guys at starlight Xpress are on the ball and they know their stuff. In particular Terry Platt. Can't say the same about the US dealers though :P

[Bassnut]

Sheesh, glad thats sorted, painfull but at least sortable.

BTW, I like the Skydrive thing youve got there for your pics, very smick (and free?). How do you find it?, is there a bandwidth limit worth worring about?.

[multiweb]

Skydrive is part of MSN. I think there's a limit on storage (approx. 100MB) but I'm not aware of any bandwidth quota. The only thing is that you need sliverlight for the slideshow but these days it's everywhere. It usually gets downloaded with microsoft updates anyway.

[gregbradley]

Wow, just what you want, shell out a couple of grand and go to Jaycar and buy some resistors, pins and soldering gear to fix it up!

Terry Platt is a good guy I agree. He helped me with the Lodestar.

Anyways, good to know its sorted.

Now, how well does it work and is it worth the trouble?

Also my Lodestar has a white horizontal line near the top of the image. Annoying as the autoselect button in CCDsoft autoguider selects it instead of the brightest star all nicely centered ready to autoguide.

Any ideas about what that may be?


Greg.

[multiweb]

Haven't tested extensively yet so I can't tell but preliminary test was very good. So yes it does work.


Funny. I have the same band at the top. Maybe an off buffer during read out? Not sure. It's not an issue for me though. Only appears with some softwares and not others.

[Enrique]

I have a SX AO LF unit. I applied the fix suggested by Terry Platt (soldering the 2.2k resistor, very simple to do).

My SX AO LF unit works from my old Dell laptop with a Centrino processor (single core) 1.7 Gh, 2 GBytes, XP SP3. I normally run the guider at 0.1 seconds. If I get a bright enough star, I could run it much faster but I do not look for them. I use the guide camera (Lodestar) with bin 2x2 that is 1.2 arcs-second per pixel. It always, up to now, shows stars that are adequate for 0.1 or 0.2 frames per second. The cpu usage does not get over 30% and the average is about 15%. I can run AstroPlaner, SkyCharts and DeepSky stacker simultaneously with the tracking software.

My USB to Serial Port converter is a cheap one sold at Jaycar ($20 or $30). I use two of them, one for the serial port of my telescope and another one for the SX-AO unit. Both converters use the Prolific driver and both work with all software I have (PHD, AstroPlaner, SkyCharts, you name it and it works!).

I am now taking 15 minutes subs and the stars are round and small. I am using a focal length of 2865 mm at F8 even with some wind. This was impossible for me to do before I started using the SX-AO unit.

I am very happy with the SX-AO unit. I am attaching a raw picture taken with a QHY8 with the gear stated above. I converted the picture to Jpeg and compressed for uploading it.

Regards,

Enrique

[bert]

Interesting, I could not get the prolific based drivers to work in vista.... Like everything else in vista I suppose....

[Enrique]

I had the telescope working with a Toshiba laptop running Vista. No problem with the USB converters. I never had a problem that I could blame on Vista. The missus took the laptop and I ended up with the old Dell. I am thinking in a credible excuse to get it back from her because it is much faster and Vista works just fine for me.

Regards,

Enrique

[Bassnut]

Thats a frame every 10 or 5 secs :P, are you sure thats what you mean?.

[Enrique]

My mistake. The guide camera is set at an exposure of 0.1 to 0.2 seconds. This is equivalent to approx 10 to 5 frames per second. Because the SX AO software has to read the CCD and do the calculations, it only can do 4 to 8 cycles per second (or corrections per second).

Thanks,

Enrique