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WP 34s USB adapters
08-25-2015, 11:40 PM
Post: #1
WP 34s USB adapters
As some of you have already found out, after about 250 USB adaptors, all of which I have soldered and tested by hand, I have recently stopped making them. The reason is, that I recently simply haven't, and probably also in future won't find the time to assemble and test them.
I am not sure how many people are still building WP34s', but at the moment I get about two requests per month. If there still was demand for a couple of hundred (which I doubt) I could probably get the boards professionally made, but I am pretty sure that would result in a significantly higher price and I am not sure if people would still be interested at 20 Euros or even more.
Alternatively I could sell bare PCBs or kits, but I think soldering the small surface mount chip might put most people off.
Quite a while ago I sold a lot of unpopulated PCBs to a forum member (not sure if he wants to be named) but so far haven't heard of him selling either boards or calculators with boards installed. Maybe he, or someone else, would like to take over the production?
I am just a bit worried about the whole project in case I stop making the boards...
On the other hand there have been a few successful approaches at making DIY flash cables by other forum members.

Any thoughts and comments are welcome.
Harald
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08-27-2015, 10:44 AM (This post was last modified: 08-27-2015 10:45 AM by 2far.)
Post: #2
RE: WP 34s USB adapters
Harald, it's good to read this! I for one am highly interested in
a) complete adapter
b) kit
c) bare PCB
in this order -- €20 for a complete adapter seems reasonable as well compared to the time for sourcing and assembling the parts.
I hope one of these options will become available!

Cheers, Greg
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09-19-2015, 09:49 AM (This post was last modified: 09-19-2015 09:50 AM by René Franquinet.)
Post: #3
RE: WP 34s USB adapters
Hi Harald

once bought two usb-adaptors from you. Now I have the problem that I cannot test if one of these is still working correctly as the 30B it has been mounted into, does not show any sign of life. I would like to see which of the two is failing: the calculator or the usb-board. Could you please provide me/us with a testing scheme in order to verify if it still does where you have made it for?

Regards,
René
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09-19-2015, 03:47 PM
Post: #4
RE: WP 34s USB adapters
Is the FTDI chip on the USB board still recognized by a host?

Greetings,

Matthias


--
"Programs are poems for computers."
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09-20-2015, 09:58 AM
Post: #5
RE: WP 34s USB adapters
(09-19-2015 03:47 PM)matthiaspaul Wrote:  Is the FTDI chip on the USB board still recognized by a host?

Greetings,

Matthias

Yes, that would have been my first question too.
Next step would be to measuer all the voltages on the pads going to the wp34s against ground. They all should be in the region of 2.5V to 3.3V. I am not sure about the rx line. that might be pulled low by the calculator when connected.

Good luck,
Harald
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10-14-2015, 08:24 PM
Post: #6
RE: WP 34s USB adapters
Hi Harald,

Can I buy a kit (bare PCB and parts) in the near future?
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10-15-2015, 08:52 AM
Post: #7
RE: WP 34s USB adapters
(10-14-2015 08:24 PM)patryk Wrote:  Hi Harald,

Can I buy a kit (bare PCB and parts) in the near future?

I am worried I might have a lot of unhappy customers if I supply that. Most peoples idea of "small" components is different from the one I have. I think over 50% of people who think they can solder the board themselves will end up with a non working board. They will know it is their fault and order another kit without complaining, but I don't like the idea of that.
So probably there won't be any kits.
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10-15-2015, 09:47 AM
Post: #8
RE: WP 34s USB adapters
I agree with Harald here. The components on these boards are small. Sufficiently small to not be solderable by a novice. I don't believe I could do it and I've been told how to deal with such fine pitch parts a couple of times.

I'm not much good at soldering but can deal with through hole components with no difficulty and can do some surface mount parts okay.


- Pauli
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10-15-2015, 02:54 PM (This post was last modified: 10-15-2015 02:56 PM by patryk.)
Post: #9
RE: WP 34s USB adapters
I can sympathize with that. But it is unfortunate for those of us who would be able to solder. I'm an EE student with plenty of soldering experience, and I'm sure I could muddle my way through to a working board.
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10-15-2015, 03:34 PM (This post was last modified: 10-15-2015 04:09 PM by Dave Frederickson.)
Post: #10
RE: WP 34s USB adapters
(10-15-2015 02:54 PM)patryk Wrote:  I can sympathize with that. But it is unfortunate for those of us who would be able to solder. I'm an EE student with plenty of soldering experience, and I'm sure I could muddle my way through to a working board.

I think all of us would like you to have a successful experience. Soldering fine pitch SMT components and opening and modifying the 30b case does require above average skills and a good microscope.

Consider making a programming cable instead, similar to the one in Katie's article which uses a different board from Harald. Harald could clarify this, but I think an equivalent could easily be made using an off the shelf USB-Serial adapter w/ 3.3V and a couple of switches. A plug can be fashioned that only needs to be soldered to the serial adapter.
https://lh6.googleusercontent.com/-LiS7b...lug+2+.jpg

Lastly, I have an unused USB board from Harald that might be available.

Dave

Edit: I have a genuine FTDI 3.3V USB-Serial cable that won't work with my HP-25E Ir in-circuit, so that might be available, too. (5V cable arrives today. Smile )
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10-15-2015, 05:22 PM
Post: #11
RE: WP 34s USB adapters
(10-15-2015 03:34 PM)Dave Frederickson Wrote:  Soldering fine pitch SMT components and opening and modifying the 30b case does require above average skills [...]

I know. I've already flashed my own stock 30b using an Arduino and installed a crystal. Saying "muddle" was just my way of being humble.

That said Dave, if you're interested in selling the USB board, I could sure use it. Which version is it (basic/IR/Lion)? And it is populated, correct?
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10-15-2015, 05:42 PM
Post: #12
RE: WP 34s USB adapters
(10-15-2015 05:22 PM)patryk Wrote:  Which version is it (basic/IR/Lion)? And it is populated, correct?

It's the IR version, but I don't recall it coming with a diode. Wasn't me that bought all the bare boards - this one has all the parts.
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10-15-2015, 06:55 PM
Post: #13
RE: WP 34s USB adapters
(10-15-2015 05:42 PM)Dave Frederickson Wrote:  
(10-15-2015 05:22 PM)patryk Wrote:  Which version is it (basic/IR/Lion)? And it is populated, correct?

It's the IR version, but I don't recall it coming with a diode. Wasn't me that bought all the bare boards - this one has all the parts.

It should have come with a diode. Unless it is one of the very early ones without the resistor for the diode, but I don't think so. If I forgot to ship the diode or if it has gone missing, they are easy enough to source though - shouldn't be a problem for an EE-student Smile
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10-15-2015, 07:43 PM
Post: #14
RE: WP 34s USB adapters
Soldering parts smaller than 0603 without solder paste and a reflow oven can be quite a challenge. On an assembly related note, here's a link to someone who built a manual pick and place machine with USB microscope and vacuum pickup for under 100USD. You would have to be populating your own boards on a regular basis to build one of these!

Low Budget Manual Pick and Place

Harald, if you're worried about the project being lost to those who might still need the board, you could always post the Gerbers and schematic to the WP34S sourceforge project. I'm awaiting the crystal and caps to build my own WP34S and wouldn't mind information on getting a bare board from you. Or, more likely, several boards given at least one failure to correctly build on my part...

~ Mark
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10-16-2015, 03:07 AM
Post: #15
RE: WP 34s USB adapters
(10-15-2015 06:55 PM)Harald Wrote:  
(10-15-2015 05:42 PM)Dave Frederickson Wrote:  It's the IR version, but I don't recall it coming with a diode. Wasn't me that bought all the bare boards - this one has all the parts.

It should have come with a diode. Unless it is one of the very early ones without the resistor for the diode, but I don't think so. If I forgot to ship the diode or if it has gone missing, they are easy enough to source though - shouldn't be a problem for an EE-student Smile

Hi Harald,

I was careful to state that I didn't recall the board including a diode, not that one wasn't included. Smile Turns out my memory indeed failed me, the Ir diode is included, and our EE-student will save some money.

Dave
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