WTB - FRAM71

[cortopar]

So sorry I missed out on these. If anyone is willing to part with an FRAM71, or there’s another run some time, please contact me here via PM.

Thanks in advance!

[burkhard]

(05-10-2018 06:20 PM)cortopar Wrote:  So sorry I missed out on these. If anyone is willing to part with an FRAM71, or there’s another run some time, please contact me here via PM.

Thanks in advance!

Yes, ditto, me too... I sent the developer an email a month or so back, but didn't get a response. I'm not certain if I had the email address right, but it didn't bounce and I think I missed the production run anyhow. Looks like a great add-on.

This (and many other such new developments) are what makes having an active forum important... You get the creative people together where they can establish critical mass and find a modest market to give them some economies of scale to make their crazy (or wonderful!) ideas come to life. It would be great if people went back to being civil and played nice.

[CY-CL]

It was not easy to find 30 orders for the first batch.

A second batch is not planed about Hans. B.

I would also buy a second one with 1MB Memory.

[mfleming]

I believe someone - Bob perhaps? - did a poll and received only about half that number of responses. Too bad, as I would like to subscribe to another run myself. It was also stated that the design was in the public domain. True?

~Mark

[rprosperi]

(05-11-2018 02:18 AM)mfleming Wrote:  I believe someone - Bob perhaps? - did a poll and received only about half that number of responses. Too bad, as I would like to subscribe to another run myself. It was also stated that the design was in the public domain. True?

~Mark

Actually I believe it was Dave Frederickson, though I can't find that thread right now, not sure where it is.

Try contacting Hans at the email address in his post here:
http://www.hpmuseum.org/forum/thread-5437.html

I am not sure if the design was made PD, however I believe Hans may share it with you if you wanted to look into making some yourself, and it appears there are some additional folks that are interested.

It would be great to have additional FRAM71 users join in the fun, hopefully this will work out.

[mfleming]

That's right, it was Dave. I couldn't find the thread either, not even the forum where it was posted. I'd love to try making the board with this sponsored project I received on Tuesday

https://www.crowdsupply.com/magicbox/reflo

Mind you, I still need to order parts for the practice boards included before I can attempt to ruin some boards & parts.

So much to do, so little time...
~Mark

[Dave Frederickson]

In February a couple of eager members acquired 71's but couldn't find F/A modules at a reasonable price and were considering FRAM71 as an alternative.

I suggested to Hans a DIY project. All that would be needed would be for Hans to fab some boards or release the PCB design files. He said it sounded interesting and asked if I had any clue as to how many people would be interested so I conducted an informal poll.

Within a week or so the number was up to about 20 boards.

Hans has already made available the programming files and BOM, under copyright. All that would be needed is the boards - and this is where it ended.

Certainly we could reverse engineer the boards if Hans abandoned the project but in light of the recent licensing discussion fiasco that's not advisable.

If Hans could be encouraged to spin more boards or release the design files then this could be a possibility.

Dave

[mfleming]

(05-11-2018 03:26 PM)Dave Frederickson Wrote:  I suggested to Hans a DIY project. All that would be needed would be for Hans to fab some boards or release the PCB design files. He said it sounded interesting and asked if I had any clue as to how many people would be interested so I conducted an informal poll.

<snip>

If Hans could be encouraged to spin more boards or release the design files then this could be a possibility.

Dave

If I could order two boards to bump the count upwards I would, but what would I do the the second one

The latest Flash5 programmer is about $51 from DigiKey, which would take care of the programming part. It would not be difficult to get some boards made if the Gerber files were available. That just leaves assembly. Other than the FPGA, the board looks pretty sparse from the pictures I've seen. Are there parts on the other side of the board (other than headers)?

By the way, if you want to see a really interesting story of someone who runs a one-man FPGA gadget company, have a look at the link below. The Updates section gives the full rundown on getting boards made, parts ordered, and boards assembled and tested by a contract manufacturer. All in volumes of low hundreds - which of course disqualifies the FRAM71!

https://www.crowdsupply.com/tinyfpga/tinyfpga-bx

~Mark

[Dave Frederickson]

(05-12-2018 02:02 AM)mfleming Wrote:  

(05-11-2018 03:26 PM)Dave Frederickson Wrote:  I suggested to Hans a DIY project. All that would be needed would be for Hans to fab some boards or release the PCB design files. He said it sounded interesting and asked if I had any clue as to how many people would be interested so I conducted an informal poll.

<snip>

If Hans could be encouraged to spin more boards or release the design files then this could be a possibility.

Dave

If I could order two boards to bump the count upwards I would, but what would I do the the second one

The latest Flash5 programmer is about $51 from DigiKey, which would take care of the programming part. It would not be difficult to get some boards made if the Gerber files were available. That just leaves assembly. Other than the FPGA, the board looks pretty sparse from the pictures I've seen. Are there parts on the other side of the board (other than headers)?

You could offer your services to assemble the board for someone without the soldering skills.

The FPGA is a VQFP packaged part under the bezel on the top side of the board. The pictures you've seen are of the bottom side of the board with the FRAM device(s), like these,

http://www.hpmuseum.org/forum/thread-251...l#pid30637


For the experienced DIY'ers you can solder the SMT parts on a stove with a frying pan.

http://www.librecalc.com/blog/souder-un-...-materiel/

The tricky part is flipping the board like a pancake for those double-sided boards. It's all in the wrist.

Dave

[mfleming]

(05-12-2018 06:47 PM)Dave Frederickson Wrote:  For the experienced DIY'ers you can solder the SMT parts on a stove with a frying pan.

http://www.librecalc.com/blog/souder-un-...-materiel/

The tricky part is flipping the board like a pancake for those double-sided boards. It's all in the wrist.

Dave

That's pretty imaginative, and I've no doubt it would work (one-sided anyway). Yield might be another question though!

I've hand-soldered fine-pitch parts and small outline passives with reasonable success though I'd probably get a B or B+ on yield. I admire those who've fully mastered those skills. It looks like Hans is one of those who does the assembly himself.

I jumped at the chance to subscribe to the Reflow oven project when it went for funding in the hope I could attempt more such projects. With low temp and high temp solder paste included in the kit, two-sided boards should be straightforward. If it comes down to just the PCBs being available I should be able to bake a few for others. As an alternative, it might be possible for Hans to re-host to an existing FPGA board, which would require only a carrier board for connection and a few parts for voltage level translation. That might put it in the realm of a wider DIY audience.

~Mark

[cortopar]

The trick is the right solder tip and using enough flux. PACE w/ wave solder tip makes SMT easy.

I taught rework classes for Honeywell, Xerox and others in the early-mid 90s. A 4 day class and you’d be very proficient.

[Paul Berger (Canada)]

(05-12-2018 10:52 PM)cortopar Wrote:  The trick is the right solder tip and using enough flux. PACE w/ wave solder tip makes SMT easy.

I taught rework classes for Honeywell, Xerox and others in the early-mid 90s. A 4 day class and you’d be very proficient.

I just watch a video about that tip, that is pretty neat, is the end slightly concaved so that it holds more solder? I have had pretty good luck using the powered solder in flux and a spade tip on a soldering iron, but have not attempted anything really fine pitched.

Paul.

[cortopar]

(05-13-2018 02:26 AM)Paul Berger (Canada) Wrote:  I just watch a video about that tip, that is pretty neat, is the end slightly concaved so that it holds more solder?

Yes, exactly. The underside is shaped a bit like a shallow spoon.

[Jlouis]

I would be interested, depending on the price. If it were the pcb for soldering, it will be ok, unless it is very tiny soldering.

Cheers

JL