1137 replies to this topic

[j21blackjack]

So I've been wanting a new mount to go with my AM5 for a while and had my sights set on the umi17 lite, but then came across this rather obscure ad on Aliexpress for a harmonic drive mount with similar specs and hardware to the AM5 and Umi17, but hundreds of dollars cheaper. I could see from the picutres it was branded Juwei-17, but Google showed absolutely nothing in search results for it. There are actually two sellers with slightly different pricing and shipping rates, so I went with the cheaper of the two and added the mount, pier extension, and hand controller to my cart to think about it for a while. Then Aliexpress dropped their March sale, and I got a $120 coupon on my order and pulled the trigger. Ordered on March 24th, delivered April 12th, not bad for Chinese shipping.

Now to the mount and initial thoughts.

Picutres: https://imgur.com/a/htxrbmF

It was packaged very well, pretty sure the tape would've held it together even if the cardboard box disintegrated, I need to order some of that orange tape they use over there. The mount head was packed nicely in cut foam packing, similar with the pier extension and hand controller.

Absolutely no instructions are included, but if you've ever put a mount together, it's the same as that, screws, centerpost, tighten bolts, good to go. I attached it to my tc-40 tripod since the AM5 is on an heq5 tripod. All of the tools needed for the hex bolts were included, so that was nice, and they look like decent tools instead of the junk metal furniture kits typically include.

I decided to try out the hand controller first, it was a nice surprise to see it was English. Took a few minutes to click through setting the time and location, then slewed it around a little. The mount is nearly silent, maybe more quiet than my AM5. I tested the wifi and Bluetooth connectivity on my Android phone with the onstep app, connected right away both ways.

Now on to the first real test and hiccup. I put my 122mm refractor on, only about 15lb, and loaded up Nina and Phd2. Quickly figured out that Bluetooth COM ports won't work with the ASCOM driver. It6might just be my mini pc, I've had trouble with Bluetooth before on it, but oh well, the included USB cord worked fine. On to the first actual hiccup, the slew speed. The default is set at a very slow 2.6 °/s, so I bumped it up to 4°/s and the motors stalled. I loaded up the onstep settings to see if I could raise the goto current, but that's not an option, so I'm stuck at 2.6 for now. I asked the seller for assistance getting the firmware file to see if I can modify the settings with that, hopefully they get back to me, but the slow slew speed isn't a really big issue as long as everything else works I guess.

I wasn't able to connect phd2 and Nina to the mount directly simultaneously, but it worked fine through ASCOM device manager. Nina reported that it failed to sync the time and locating, but it did actually update the mount, probably just a communication error.

It's a clear night tonight, should have some results in a few hours.

Edited by j21blackjack, 12 April 2024 - 04:01 PM.

[j21blackjack]

Well, first 5 minute exposure looks pretty good. My guiding is hanging out around 0.8" RMS, it's slightly windy tonight. Shooting M106 with my Svbony sv550 122mm, Askar oag and filter drawer, Antila triband ultra rgb filter, and the Juwei-17 mount.

I took off the sides of the mount to look inside. It looks very clean with just the two motors, belt drives, side panel, and onstep controller board. I can't tell what stepper drivers they used, I asked the seller for that info as well. The slow slewing speed hasn't bothered me, I typically only shoot one or two targets a night anyway.

Here's screenshots and some pictures of the inside of the mount.

https://imgur.com/a/7x9K9a1

[j21blackjack]

And first image is done and posted on Astrobin. I had to create an entry for the Juwei-17 mount since it didn't exist yet.

Guiding held great at 0.6 to 0.8. I made a classic mistake and didn't check my clearance at zenith, so my scope contacted the tripod leg on the meridian flip and failed to center and restart imaging. At least I got a few good hours in before the meridian.

https://www.astrobin.com/z0bwir/

Edited by j21blackjack, 13 April 2024 - 10:19 AM.

[Ljubo]

Congrats! Great initial results... 

 

I have my Juwei-17 at customs at the moment, awaiting for delivery early next week.... In your opinion, should it be able to carry an C9.25 XLT, too (with CW, of course)? If so, that may be great mount for the galaxy season we're in.

 

Are there anything I should care in particular when setting the altitude and azimuth? (I will put it on an HEQ5 tripod with an adapter from the same Ali store). It will be nice if you can put that instruction video somewhere on the net, although I think the procedure of setting the mount should be straight).

[j21blackjack]

Congrats! Great initial results...

I have my Juwei-17 at customs at the moment, awaiting for delivery early next week.... In your opinion, should it be able to carry an C9.25 XLT, too (with CW, of course)? If so, that may be great mount for the galaxy season we're in.

Are there anything I should care in particular when setting the altitude and azimuth? (I will put it on an HEQ5 tripod with an adapter from the same Ali store). It will be nice if you can put that instruction video somewhere on the net, although I think the procedure of setting the mount should be straight).

The 9.25 technically should be fine with the CW. My AM5 stalls occasionally with my 9.25 on it, normally only if I put extra stuff on the top bar though. The pier extension actually came with an heq5 adapter if you ordered that. Mine still showed it was at customs when it got delivered, so hopefully yours gets there soon too.

Theres nothing outside of the normal when setting the mount up, I think the UTC offset is backwards than usual, mine shows +5 even though I'm -5, but that's ok with me as long as it works.

Watch your scope near zenith, mine hit the tripod last night on the meridian flip, scope at 72 altitude. I should've checked the clearance. This of course wasted about 4 hours of exposure because the guiding was thrown off and it never centered after the flip.

Edited by j21blackjack, 13 April 2024 - 01:19 PM.

[j21blackjack]

Just a side by side with the AM5 

 

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[Ljubo]

Very nice!  

 

Is it possible to mount Juwei-17  on ZWO PE-200? And if it can, is the PE-200 better option (quick mount remove, great capacity) as their end prices are practically the same?

Thanks.

[Skywatchr]

Just a side by side with the AM5 

I really love the blue/silver anodizing over the red that fades to pink over time.

[j21blackjack]

Very nice!  

 

Is it possible to mount Juwei-17  on ZWO PE-200? And if it can, is the PE-200 better option (quick mount remove, great capacity) as their end prices are practically the same?

Thanks.

Unfortunately they do not appear compatible at all. The pe200 is just an open hole with the side locking screws, so you have to somehow adapter an AM5 plate to the bottom of the Juwei-17, but there doesn't appear to be any way to do that either. 

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[Cbaxter]

When you ordered all three items, did it charge you shipping for each individual? It wanted to charge me ~$85 per item which would mean paying $85 shipping on a $60 handset.

[j21blackjack]

When you ordered all three items, did it charge you shipping for each individual? It wanted to charge me ~$85 per item which would mean paying $85 shipping on a $60 handset.

Nope, I ordered from the other store for this reason, it's under the Dazzling Photoelectric Store, not the other one. The mount is the only thing that isn't free shipping, the pier and hand controller are both free shipping. The hand controller has its own listing since you can't order it from the mount page.

Here's the hand controller:
https://a.aliexpress.com/_mOBVs7k

Here's the mount:
https://a.aliexpress.com/_mMUezC6

Edited by j21blackjack, 15 April 2024 - 06:09 AM.

[Cbaxter]

Nope, I ordered from the other store for this reason, it's under the Dazzling Photoelectric Store, not the other one. The mount is the only thing that isn't free shipping, the pier and hand controller are both free shipping. The hand controller has its own listing since you can't order it from the mount page.

Here's the hand controller:
https://a.aliexpress.com/_mOBVs7k

Here's the mount:
https://a.aliexpress.com/_mMUezC6

Perfect! Thanks! Ordered blue one. I currently have iOptron HAE43 and was looking at the smaller iOptron and ZWO but this direct from China price is almost half of the others so I'll take the chance on it.

[Starlancer]

Definitely interesting for the price!  You might be able to increase the current by tweaking trimmer pots on the drivers themselves.  

[j21blackjack]

Definitely interesting for the price! You might be able to increase the current by tweaking trimmer pots on the drivers themselves.

There is access to the trimmer pots through the board so that's good. My response from the seller was to not to increase goto speed, but 2.6°/s definitely feels pretty slow. I need to figure out which stepper drivers these are, and of course they are soldered in so it will be a pain to swap them out. I'm planning on putting 5160s in if I can get the firmware file from them.

Edit: the steppers are TMC2208

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Edited by j21blackjack, 16 April 2024 - 10:33 AM.

[Starlancer]

TMC2209 should be a direct replacement and get almost an extra amp at peak.

[j21blackjack]

TMC2209 should be a direct replacement and get almost an extra amp at peak.

I would agree, but the motors are only 1.3a rated, and the 2208 is rated at 1.2a continuous output, so you don't need much more than what it can give anyway. What I want to do is swap out to 5160s since the 2208 is locked in stealthchop mode, with no spreadcycle. Makes sense why it's so quiet, because that's all it can be.

Did some more measuring, the original setting of the 2208 vref (which is peak current) is only 345ma RMS (the AM5 peak current is 1.7a by comparison). According to the onstep group, standalone stepper drivers, like the 2208 and 2209, vref is set based on peak current. Most of the calculators talk about RMS current, so I just set mine to 1v to be safe. Hopefully that will bump the goto current up closer to the motor limits and maybe even allow for a higher slew rate. I also put some heat sinks on the stepper chips since none were installed, there's plenty of room inside the box for them.

Still waiting on a copy of the config.h file and circuit diagram. The circuit isn't hard to figure out, but there's some dip switches on the board that I'm guessing are used to enable flashing the onstep board and hand controller board. I just want to disable that tracking on startup mess, really screws up polar alignment if I'm not paying attention.

Edited by j21blackjack, 16 April 2024 - 01:17 PM.

[Starlancer]

I assume you've liked the mount otherwise.  I am looking for a second mount and for the price this fits the bill.  I have an AM5 now and really like the harmonic mounts.  The WD-17s looks nice but double the price.  I've also looked at the UMI17 but it looks quite similar to this mount  and cost more.

 

Also does it support an Alt-Az mode?  I looks like it would have plenty of clearance, I guess it's a matter of onstep programing at that point.

[j21blackjack]

I assume you've liked the mount otherwise. I am looking for a second mount and for the price this fits the bill. I have an AM5 now and really like the harmonic mounts. The WD-17s looks nice but double the price. I've also looked at the UMI17 but it looks quite similar to this mount and cost more.

Also does it support an Alt-Az mode? I looks like it would have plenty of clearance, I guess it's a matter of onstep programing at that point.

I like the mount very much so far, guiding was great both nights that I used it wiry my 122mm refractor. It is listed as 10 to 90 degree, so maybe with some onstep settings it could be Alt/AZ compatible.

[leaponover]

Wanted to thank you for providing this info.  I'm thinking about picking one of these up, and you are the only review in town, lol.  Please keep us posted periodically on the performance.  I've got some saving to do before I pull the trigger.

[Starlancer]

I would agree, but the motors are only 1.3a rated, and the 2208 is rated at 1.2a continuous output, so you don't need much more than what it can give anyway. What I want to do is swap out to 5160s since the 2208 is locked in stealthchop mode, with no spreadcycle. Makes sense why it's so quiet, because that's all it can be.

Did some more measuring, the original setting of the 2208 vref (which is peak current) is only 345ma RMS (the AM5 peak current is 1.7a by comparison). According to the onstep group, standalone stepper drivers, like the 2208 and 2209, vref is set based on peak current. Most of the calculators talk about RMS current, so I just set mine to 1v to be safe. Hopefully that will bump the goto current up closer to the motor limits and maybe even allow for a higher slew rate. I also put some heat sinks on the stepper chips since none were installed, there's plenty of room inside the box for them.

Still waiting on a copy of the config.h file and circuit diagram. The circuit isn't hard to figure out, but there's some dip switches on the board that I'm guessing are used to enable flashing the onstep board and hand controller board. I just want to disable that tracking on startup mess, really screws up polar alignment if I'm not paying attention.

If you happen to get the firmware please drop it here, would be great for future reference. 

[KemalOz]

Thanks for the review. There is very little info about these new Chinese mounts. I hope someone eventually makes a comparison between the Umi17, Umi17 lite and the Juwei-17. I really like the form factor of Umi17 lite as a travel mount. 

 

Does onstep support encoders? Maybe we will see a Juwei-17 EC in the future. 

[j21blackjack]

If you happen to get the firmware please drop it here, would be great for future reference.

Will do, but I'm not holding my breath on getting the source code, the Chinese aren't well known for following the rules of open source licenses. The only thing they've sent me is a bin file to disable tracking on startup. They've ignored my request for the source code so far.

I went ahead and just ordered an FYSETC E4 assuming they're never going to send me the code. It's easy to adapt to any system pretty much, as long as it fits inside the mount, it'll be good to go.

Edited by j21blackjack, 17 April 2024 - 01:05 PM.

[j21blackjack]

I was able to get a firmware version that disables the tracking autostart, it wasn't too terrible to flash. The maker included a set of dip switches to enable flashing. The firmware files are bin files with a bat file that automates the flashing, pretty simple.

[Skywatchr]

Where else besides AliExpress might these be available?

[Cbaxter]

Where else besides AliExpress might these be available?

Nowhere that I am aware of. FWIW, I've ordered many times from AE, paid with PayPal, and the only "issue" I've ever had is a long shipping time. One time shipping took so long that was given a 100% refund on the item then when it eventually showed up I got to keep it. Shipping is usually pretty fast considering the origin and customs clearance.

Edited by Cbaxter, 18 April 2024 - 05:57 PM.