Source of peculiar mini-DIN 8 surface mount socket?
Hi all
My Tak Temma 2 Jr is suffering nasty & somewhat sporadic hand box problems. The hand box's cable is OK (proven it by turning it around), but the 8-pin surface-mount mini-DIN socket within the controller itself... she is broke. You plug in and wiggle the cable within the socket, and the NS/HS bi-colour LED on the hand box turns on/off when you do. Problem with this is that you need the hand box connected and switch S1 held in on power-up to initialise the Temma into southern hemisphere mode. This is a problem.
I've just been scouting around the electronics shops (Jaycar, et al) and an finding that they don't carry such sockets. The socket is a particular type that has a bolt-hole at the top, which is necessary to clamp the board down with inside the controller casing and offer strain-relief. I can get the normal flanged case-mount mini-DIN sockets 'till the cows arrive home, but not the surface mount. Can anyone help out here and advise me on a source for these locally? Otherwise, I'm going to have to either send the Temma Jr controller to Japan or order a replacement from Tak spares. Ow!
Also - a question to Temma 2 Jr owners - with the RS-232 cable plugged in (and talking to a computer) should the hand box still work? I can't slew anywhere with the hand box when the Temma's plugged in to an external device. Is this normal?
The control box still works when connected to the sky via rs232 on mine. I have sourced 4 and 6 pin mini din plugs from jaycar already for the guider and 232 cables. If they don;t have it rs components will. Problem there is finding it in the cattledog, it is huge and finding one with that loop on top might be a problem. We recently got pcb mount usb sockets from there for a qhy5.
Thanks Robin - RS do have surface-mount mini-DIN 4,6 & 8-pin sockets that I need to replace all the Temma sockets. They don't have the bolt-hole, so I'm going to have to work out a way to secure the board to the case. You need to do this because the board and sockets support the weight of the four cables plugged into it.
If it comes to the crunch, I'll have to go with these I think.
Thanks re; the RS-232 issue. Maybe the bad plug is holding a signal high or low, killing the hand box when the RS-232 is plugged in. I have no problem talking to the computer and guiding too, just the hand box is a problem.
Sorry to hear of your woes, this just should not happen on these expensive mounts!
In terms of operating the motor movement buttons S3, S4, S5 and S6 on the hand controller whilst the mount is synchronised to and being commanded by a planetarium program, for my EM200 Temma II the answer is yes, I can do this and it is an important part of my alignment and synchronisation routine.
I often touch up the centring of an object, either using the physical keys on the hand control unit or the virtual keys on the ASCOM panel and then sync with the application.
If I press and hold S2 on the hand controller whilst manually jogging S3, S4, S5 or S6 to manually centre an object, the commands from the hand controller are not fed back to the planetarium program.
Let us know if you find a suitable replacement connector, as I might get one as a spare just in case. I have had to jam a rubber wedge into the cable entrance port on my hand controller to apply sideways pressure to the incoming cable/connector assembly; otherwise I suffer intermittent electrical contact at the hand controller end. In my case, it appears that one of the actual pins on the connector is some how floating in its female receptacle, requiring sideways pressure from the rubber wedge for it to make contact.
Thanks for that Dennis, and yes, same here - sideways pressure seems to re-connect the box...sometimes. If I replace the entire 8-pin hand box socket and leave the 6-pin one on the end (autoguide port) with its bolt hole to secure the board, I may replace the motor control switch with one that has a threaded shank/nut so that it can, as well, offer mechanical support. At the moment it just floats through the hole in the case. I hope that this won't introduce a ground loop problem...
A tad dicky for, as you say, a mount such as this. I'm going to look into constructing a bolt-on cable clamp rack that will relieve stress on the mini-DIN sockets from the weight of the four cables and as the cables flex during the night - especially when stiff because they're cold.
Chris, are you sure it's not a fractured solder joint on the double sided PCB?
These are very similar unit's to music FX units, they almost never need replacing. Try to run solder down each joint so as contact repair is done to the upper & lower tracks. If not I would get a mini8 Female lead end and solder the cable to the PCB with a short length of cable protruding. Hold it down with a cable tie to the PCB.
Any connector soldered to a double sided PCB is very difficult to remove without damaging the pads and hole through joints.
Roland (music equipment) would most likely have these PCB mount sockets.
The best way to remove these is by making a mask of thick cardboard so just the sockets solder joints are exposed and use a heat gun (so all solder joints turn liquid at the same time).
Thanks David - good advice. I will certainly re-apply heat to re-wet the joints. I'm also going to try contact cleaner to see if it's just a grunge layer that's adding to the trouble. It looks like the hole-through quality is pretty good, and I reckon that it won't be much trouble to remove the socket without damaging them. There are no sensitive LSI's on the board - not even any TTL, it's purely for electrical connections.
Well... she's out. Nice and easy. The through-hole plating is very good quality - nice and thick and it stood up well. Now to source a replacement socket - with or without mounting hole.
Hi Chris
I bought some of those mini DIN plugs online from Mouser Electronics a couple of months ago for my old EM200. Mine may not be the same as yours but I did get a match.
Thanks Guy. I just had a look at mouser.com and it looks as though the package types are different. My main problem is that I need the single post at the front for the PCB mount. I take it that your EM-200 is a Temma 2 and not a Temma 2 Jr, no?
no
it is a non goto EM200b pre USD mount I think, but it seems to use a similar plug for the control pad - see pic of original. I also got another DIN plug for an FLI power supply from Mouser.
Might be worth sending a pic to Mouser - they are very helpful I've found.
guy
We recently got pcb mount usb sockets from there [rs components] for a qhy5.
A friend did the same repair for me with a spare from rs components as well. Lesson : be very careful plugging and un-plugging QHY5 USB cable in the dark. The repair is not for the faint hearted - hot soldering iron just a few mm from the CCD chip.
James
