I should have been clearer. I tested without U1 and without power.

See the attached pictures (sorry for the very narrow depth of field!). It does seem to me the tracks are joined, I'm unsure if that would cause the problems I'm having.

Attached Thumbnails

   

 

hi,
Thats a copper track bridge for sure, use a small scalpel blade to cut the bridge.

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I'm not sure the pictures do it justice, the gap between those tracks is very small and it's wedged between the two sockets! It will be very difficult to cut it without going through one of the tracks

I'll have to work up the courage to play with knives. I actually think there might be another (not quite so bad) on the bottom of the board too.

 

Wow I'll have to check my PCB stock for that bridge, sorry about that I'll have to see what my PCB supplier can do about that. I do leave generous spacing between traces so it must have been something at the PCB shop.
A few cuts with an xacto will fix it, take your time and it should be fine. When I've done it a slow steady cut or two (and a steady hand) will do it. I'm sorry it caused you so much trouble.
Where do you think the other one may be?

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Under SW5. I've attached a picture, it's cropped so nobody can see more of my awful soldering

I have scraped away the blue covering this time to get a good look.

Attached Thumbnails

 

 

Finally, a post to be happy with.

I made a bit of a mess with the cutting (scored the coating off 1 track) but I got rid of the bridge and didn't cut through either of the proper tracks.

See the photo below, which shows the LED flasher program from the Junebug manual working happily. There appear to be two LEDs on at once due to the slow exposure

However, the photo also shows a missing BS250. I have a replacement here but don't know which lead is which, I'll post a message over in the datasheet request forum if anybody can help. That's the last thing to fix before I start playing with it properly.

Thanks for all the answers, it's great to have it working.

Attached Thumbnails

 

 

Glad to hear you found the problem and got it working, I've been examining the Junebug PCBs for bridges and it seems you've got the only one so far. There is a diode in the BS250 across the drain & source, an ohmmeter will spot it.
The new Junebug manual shows the orientation of both BS250 types.

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Thanks Bill. If you could confirm that the one I bought is compatible (180mA not 250mA) that would be great, I'll check for the diode.

 

180ma is fine, keep the jumper in place unless you need VDD before VPP programming (only required for some very specialized PIC config modes)

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Hi,
I seem to be having the same problem as Edeca had. I picked up an assembled Junebug from Creatron last summer (2008). Finally, tried it out recently and when I connect to the PicKit2 software, I get a VPP error. It is the same scenario as Edeca's first post. When I run PICkit2 v2.61 software I immediately get a VPP voltage level error. I can assign an ID to the Junebug, but cannot send a program to it or read what's on the chip. When I run the Troubleshoot option, I'm able to measure proper voltages with a voltmeter. In Troubleshoot Step 2, when I have /MCLR On and then click Test VPP, a short is detected.

Since I purchased it assembled, I'm hesitant to begin desoldering and pulling off components to look for copper cross-overs like Edeca found. There are no visible cross-overs on the bottom of the board at least.

Bill, do you have any particular places you recommend looking for issues?

Thanks, Tom

 

A handfull of the first Junebugs built by Creatron had two resistors swapped in the VPP section. Check the PCB silkscreen & partslist against your kit.
The PCB problem is very rare. I'm on my mobile but I'll see if I can give a detailed response this afternoon.

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I see you're in Waterloo deputy, do you get to the GTA often? If so just drop the Junebug off at Creatron and tell Lawrence it's for Bill to fix and I'll drop in and fix it.

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Hi Bill,
I'll be in Toronto for something this weekend.
I'll drop the Junebug off at Creatron Sat morning.
Thanks for the help!

 

Ok I'll pick it up and keep you posted on what was wrong with it. I'll get it fixed ASAP.

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Fixed, do you want it mailed via Canada Post or dropped off at Creatron?

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