Return-to-zero shift register FIRDAC

Thanks for working on this for us Marcel.

I've not had problems with ufl connectors but have only used them in 'install and forget' situations so happy to use them in this scenario - I can use the Amanero header for testing and then switch to ufl for the final build.
 
  • Like
Reactions: 1 user
I would opt for SMA/B or MMCX connectors.
I have used MMCX connectors for some time now with some of them expericiencing well over 100 re-connects. They are a tight fit at first but loosen up. They should not be placed too close to each other as disconnecting with fingers or tools requires space around them. I have placed them about 6mm apart (centerpin to centerpin) but that is about the minimum. If space allows 10mm would be much better.
 
Could those of you who have experience with U.FL connectors tell me if this placement is acceptable?
It would be nice if the three connectors could be aligned towards the board edge, maybe between P1 and R3, though I guess that may have consequences for theinner PCB layers?
 

Attachments

  • Capture.JPG
    Capture.JPG
    69.8 KB · Views: 63
For better or worse, u.fl is what I see other's use for this application. Iancanada uses u.fl

I bought maybe 100 little u.fl cables from ebay, so when I take my stack apart, I throw the cable away and use a new one every time so I don't worry about the connector.
You should also try and be as square as possible when you connect or disconnect, but its hard to do.

Randy
 
If possible, I could use some spare filter boards.

nautibuoy - 3 sets
pgour - 1 set
Raj1 - 1 set
rfbrw - 2 sets + 2 filter boards.
wealas - 1 set
barryblue - 1 set
randytsuch - 2 sets
Mich - 1 set
Sonnymarrow - 2 sets
Twinkletoes - 1 set
porcupinetrain - 1 set
NickKUK - 1 set
manniraj - 1 set
 
  • Like
Reactions: 1 user
No problem, I can order a few extra filter boards.

I'll await Marcel's deliberations on the ufl topic/location to finalise the buy but a quick estimate at the PCB fabricator for 20 DAC PCBs and 20 Filter PCBs is coming out at around $160 delivered to me, so cost will be around $8 per set plus the cost of onward shipping.
 
Hi everyone. It looks like we're getting close to initiating the group buy so it would be helpful if you could check and amend your requirements in the list below so I know how many boards to order. I'll set up and share a spreadsheet to coordinate the GB when I have a bit more time.

Based on previous experience of group buys (where there have ben people who don't follow up on their interest or generally drag their heels) I will expect an up-front payment from buyers before I place the order (so that I'm not left out of pocket) and I will set specific dates for responses/payments, after which we'll move on without stragglers. I hope that is OK with everyone?

Nearly time to start ordering parts I think.

Marcel - 2xDAC, 2xFilter (FoC)
nautibuoy - 3xDAC, 3xFilter
pgour - 1xDAC, 1xFilter
Raj1 - 1xDAC, 1xFilter
rfbrw - 2xDAC, 4xFilter.
wealas - 1xDAC, 1xFilter
barryblue - 1xDAC, 1xFilter
randytsuch - 2xDAC, 2xFilter
Mich - 1xDAC, 1xFilter
Sonnymarrow - 2xDAC, 2xFilter
Twinkletoes - 1xDAC, 1xFilter
porcupinetrain - 1xDAC, 1xFilter
NickKUK - 1xDAC, 1xFilter
manniraj - 1xDAC, 1xFilter
 
  • Like
Reactions: 1 user
I believe it is 3.5mil Marcel - check out the PCB specs on the link I PM'ed you last Friday.

I did, and I read what their capabilities are, but not if those add extra costs. For example, at Eurocircuits, line widths down to 0.09 mm are allowed, but anything narrower than 0.15 mm will cost you extra money.

At the moment the minimum track width is 0.25 mm, but there are a couple of short tracks I would like to change into 0.15 mm. Hence the question.
 
I did, and I read what their capabilities are, but not if those add extra costs. For example, at Eurocircuits, line widths down to 0.09 mm are allowed, but anything narrower than 0.15 mm will cost you extra money.

At the moment the minimum track width is 0.25 mm, but there are a couple of short tracks I would like to change into 0.15 mm. Hence the question.
I read the 3.5mil as an absolute minimum (and essentially the same as the Eurocircuits 0.09mm limit), but I couldn't see any reference to additional costs below a certain track thickness so I think the only way to find out will be to load up the finalised gerber files and get a price. I don't imagine any extra cost will dramatically change the overall pricing, but we'll see.