HELP. Troubleshooting Skywatcher EQ3-2 Synscan GOTO

[Varavall]

Hi all

I need some help with troubleshooting this problem:

1. Connect EQMOD cable to mount and all works perfectly

2. Connect handset from my SW HEQ5 and I get the "both axes no response" message

3. Connect EQMOD cable to mount and get failure to connect

4. Connect handset to HEQ5 and it works perfectly

5. Connect EQMOD cable to HEQ5 and it works perfectly

6. Inspect Synscan motherboard with magnifying glass and can see no sign of blown components.

 

All comments welcome! It is not under warranty.

Thanks in advance

Adrian

[malc-c]

The no response message basically means that the handset  (and EQMOD) doesn't receive a response to the initial message sent by the handset / EQMOD to find out what motorboard it is communicating with.  You don't mention if you powered down the mount between swapping handsets and EQDIR cable (swapping them whilst powered up is a good way to blow the motor board).

There is nothing damaged with the board as you state in options 4 and 5 that communication is established / re-established.  I would advise you stick with using either just the handset or just the EQDIR cable.  The firmware is expecting one or the other to be connected at power up.

[Varavall]

3 hours ago, malc-c said:

You don't mention if you powered down the mount between swapping handsets and EQDIR cable

Thanks for the response. Yes, always powered off whilst swapping cables.

 

3 hours ago, malc-c said:

The firmware is expecting one or the other to be connected at power up.

 

3 hours ago, malc-c said:

I would advise you stick with using either just the handset or just the EQDIR cable. 

That's the problem. Neither EQDIR cable nor the handset works now with the EQ3-2 mount.

[malc-c]

17 hours ago, Varavall said:

Hi all

I need some help with troubleshooting this problem:

1. Connect EQMOD cable to mount and all works perfectly

2. Connect handset from my SW HEQ5 and I get the "both axes no response" message

3. Connect EQMOD cable to mount and get failure to connect

4. Connect handset to HEQ5 and it works perfectly

5. Connect EQMOD cable to HEQ5 and it works perfectly

6. Inspect Synscan motherboard with magnifying glass and can see no sign of blown components.

 

All comments welcome! It is not under warranty.

Thanks in advance

Adrian

 

1 hour ago, Varavall said:

That's the problem. Neither EQDIR cable nor the handset works now with the EQ3-2 mount.

 

But you mention an HEQ5 - no mention of EQ3-2....   If the fault lies with an EQ3-2 then why confuse matters by stating the HEQ5 in your original post ?

If an EQDIR cable and a Handset fails to connect to a Synscan unit then the chances are that the synscan has a fault.  This is either blown diodes (by that there will be no physical signs of damage, but the internal part has gone) on the TX/RX lines, or the serial UART on one or both PIC microcontrollers have been damaged.  Have a read of this thread which may give you some assistance.  If your sysnscan unit on the eq3-2  has a USB B port then ignore the suggestions in that thread - the newer units have an ARM processor and programming one of these and replacing it is a more specialist task than most home users.

[Varavall]

2 minutes ago, malc-c said:

 If the fault lies with an EQ3-2 then why confuse matters by stating the HEQ5 in your original post

Because that is the order in which I verified that there is no problem with the handset or EQDIR cable.

 

3 minutes ago, malc-c said:

Have a read of this thread 

I'll take a look. In my gut I think the something has fried.

 

Thanks for your comments

[malc-c]

19 minutes ago, Varavall said:

Because that is the order in which I verified that there is no problem with the handset or EQDIR cable.

I'm still confused (easily done) - because after points 4 and 5 the mount (presumably handset) is left in a working state.  But having said that I think I see where the confusion is.  Should the description have read ?

2. Connect handset from my SW HEQ5 to my EQ3-2 and I get the "both axes no response" message

3. Connect EQMOD cable to my EQ3-2 and get failure to connect

4. Connect the same handset to HEQ5 and it works perfectly

5. Connect the same EQMOD cable to HEQ5 and it works perfectly

6. Inspect Synscan EQ3-2 motherboard with magnifying glass and can see no sign of blown components.

PS

If you have one of the older syscan boards which have 2x 16F886's but lack the option to program them drop me a PM and we'll try and sort something out.

Edited June 21, 2022 by malc-c

[Varavall]

2 hours ago, malc-c said:

Should the description have read ?

2. Connect handset from my SW HEQ5 to my EQ3-2 and I get the "both axes no response" message

3. Connect EQMOD cable to my EQ3-2 and get failure to connect

4. Connect the same handset to HEQ5 and it works perfectly

5. Connect the same EQMOD cable to HEQ5 and it works perfectly

6. Inspect Synscan EQ3-2 motherboard with magnifying glass and can see no sign of blown components.

Yup, you got it right.

2 hours ago, malc-c said:

If you have one of the older syscan boards which have 2x 16F886's but lack the option to program them drop me a PM and we'll try and sort something out.

Thanks for the offer; I'll post a photo of the board and perhaps you can tell me what I have. I'm afraid electronics to me is a black art, but, nuclear explosives and synchronising global computer networks are a cinch in comparison 😁

[malc-c]

1 hour ago, Varavall said:

Yup, you got it right.

Thanks for the offer; I'll post a photo of the board and perhaps you can tell me what I have. I'm afraid electronics to me is a black art, but, nuclear explosives and synchronising global computer networks are a cinch in comparison 😁

 

Yes, post up some pictures.  I'm confident the unit is an older PIC based unit given the fact it's out of warranty and you use an EQDIR cable rather than a USB cable.  The newer revisions have a USB-B type port in them (with a TTL Serial to USB convertor chip like that used in an EQDIR cable internally )

[Varavall]

On 21/06/2022 at 18:59, malc-c said:

 

Yes, post up some pictures.  I'm confident the unit is an older PIC based unit given the fact it's out of warranty and you use an EQDIR cable rather than a USB cable.  The newer revisions have a USB-B type port in them (with a TTL Serial to USB convertor chip like that used in an EQDIR cable internally )

Here they are! I await news from the oracle 🙂

[malc-c]

Excellent, yes that is an older board, with the PIC16F886 -

How good is your soldering skills ? - the old chip can be removed using a dedicated hot air gun, or you can carefully cut the legs off using a dremel with a cutting disk, and the  remove the legs using a soldering iron.  If that's not an option, do you know of any local repair shop, or company near you that could remove and resolder a new chip in its place ?  If so drop me a PM and we can sort out getting a replacement programmed and sent to you. 

[Varavall]

On 23/06/2022 at 00:03, malc-c said:

How good is your soldering skills ?

Not well practiced! I assume it's the chip with the red splodge on it?

 

On 23/06/2022 at 00:03, malc-c said:

do you know of any local repair shop

I believe there are some in nearby towns, so I'll ask around and see what's doing. If nothing, I guess its a soldering iron and Dremel from Amazon; nothing to lose, just honing a skill.

Many thanks for your assistance, it's much appreciated.

Edited June 24, 2022 by Varavall

[malc-c]

Yes it's the SOIC with the red blob on it that needs replacing.  As I said it's not difficult to replace them, but you are really jumping in the deep end if you've never soldered before.  Soldering the new one is the easy part, removing the old one without damage to the pads or tracks on the PCB is the tricky part.  Any business offering PCB fabrication, or even a decent TV repair centre that repairs to component level should be able to do the swap with their eyes closed

A good quality flux also helps to get the solder flowing, and avoid lead free solder if possible