Woodstock Low Power

[BobVA]

Yay! Thank you for the fantastic Christmas present :-)

[rprosperi]

(12-03-2017 11:13 PM)Geir Isene Wrote:  

(12-03-2017 05:27 PM)PANAMATIK Wrote:  Woodstock Low Power hardware finally is available!

Although I could need a break now, I will process all orders as soon as possible and hopefully give you a really nice new LED calculator for christmas.

Thanks
Bernhard

Fucking awesome!

You simply have a way with words Geir! Concise, accurate, conveys all the right emotion!

[PANAMATIK]

First Woodstock LP item shipped!

Today I went to post office and shipped the first LP circuit. Six more circuits are tested and ready to ship on my table. But the orders surprised me. I have to order more bare boards and GPS modules , not all orders can find the way under the christmas tree in time. I'm sorry. But I will proceed as fast as I can. Nevertheless this is the production hell, now I know what Tesla is talking about. In my case the manual work will persist, no mass production at all. Lot of soldering and testing. But I hope you will enjoy the result.

Bernhard

[Didier Lachieze]

It seems that in 2017 Santa Claus has been busy releasing new RPN calculators: NP-41, DM-42, Woodstock LP.

I had to make some tough choices, and I will relieve some pressure from you Bernhard and from Santa’s elves, I will delay my Woodstock LP order to next year. I want to have enough time to fully enjoy your new marvel.

[PANAMATIK]

(12-08-2017 12:57 PM)Didier Lachieze Wrote:  It seems that in 2017 Santa Claus has been busy releasing new RPN calculators: NP-41, DM-42, Woodstock LP.

I had to make some tough choices, and I will relieve some pressure from you Bernhard and from Santa’s elves, I will delay my Woodstock LP order to next year. I want to have enough time to fully enjoy your new marvel.

And don't forget the multi calculator kit from teenix. Although I don't know whether it will be available before christmas.

Bernhard

[BobVA]

Quote: But the orders surprised me.

I'll bet! I predict for your next project we'll be camping outside the fabulous glass-walled Panamatik retail store and getting interviewed by DW :-)

Just to clarify: to place an order we just need to send it your "sales" address, correct? And you'll acknowledge / provide payment instructions for those as you work your way through the queue?

Thanks again for all your work on this project! It's beyond cool!

[hewlpac]

Came home from a trip to Mexico to calculator nirvana:

[attachment=5450]

Original HP-27
ACT replaced HP-27
Full brain transplant HP-27 LP

[Maximilian Hohmann]

I knew it: The sun shone through our windows onto my table this afternoon (which means I could have done the soldering without using a loupe or glasses), the soldering iron was hot, the Panamatik parts were disposed around my workplace, I had disassembled two Woodstocks (a 21 and a 25) for a last-minute decision which one to sacrifice.
Then I took up the x-acto knife in order to inflict the PCB-sectomy on one of the calculators. But I couldn't do it. However hard I tried. A cosmetic surgeon must feel that way when tasked with cutting up a perfectly beautiful face to (allegedly) make it even more beautiful...
So I unplugged my soldering iron again, reassembled the calculators, put the tools away and bought a "defective" HP-22 on eBay instead from the UK. Should be here end of next week so I can try again next weekend. But with my kind of luck that defective HP-22 will probably work just fine and I will be back were I am now ;-)

Regards
Max

NB: In the process I discovered that the rubber feet of most of my Woodstocks have turned into something like chewing gum over the years. Which means that they will be destroyed when the screws underneath need to be accessed. Has anyone come up with something to replace those feet with?

[PANAMATIK]

(01-06-2018 05:57 PM)Maximilian Hohmann Wrote:  .... But I couldn't do it....

Very nice story and absolutely the right decision. The main intention of the LP circuit was still the repair of a defective Woodstock calculator. Keeping an original working machine alive is highly appreciated. But what if there are no defective Woodstocks any more out there? The LP circuit will be buried in oblivion.

I was very slow in delivering, because all boards have been sent back to the manufacturer in mid december for professionally soldering the processor. They returned the day before christmas. But I didn't have time to finish them until this week. Since a few days all LP circuit orders have been sent to the "customers". I hope the surgery will be successful for all and I'm eager to get feedback about some possible difficulties and hopefully all successes.

BTW the LP source code can be downloaded from my website.

(01-06-2018 05:57 PM)Maximilian Hohmann Wrote:  NB: In the process I discovered that the rubber feet of most of my Woodstocks have turned into something like chewing gum over the years. Which means that they will be destroyed when the screws underneath need to be accessed. Has anyone come up with something to replace those feet with?

My experience is that about 10-20 % of the rubber feet mutated to chewing gum. Perhaps it depends on temperature or humidity during storage? Horst Hoffmann successfully used some shoe heel rubber as a replacement, which can be found in the same or similar beige color.

Bernhard

[Harald]

My Woodstock LP kit has arrived a few days ago. I dug through my box of Woodstocks and think I found the right parts for the job. A non working 25c PCB which I already desoldered most of the usable parts from. It has a separate power supply board so that can be removed as well. Then I found a decent HP27 keyboard. Hopefully that is compatible with the 25c main PCB. I would like to use it because it doesn't have a switch that would be dead after the transplant.
I will nick the GPS receiver and smps from an already converted Woodstock.

I'll post here when the job is done.

Cheers,
Harald

[Paul Dale]

I'm not sure I've got a non-working Woodstock. I think all of mine work still


Pauli

[Dieter]

(01-06-2018 05:57 PM)Maximilian Hohmann Wrote:  NB: In the process I discovered that the rubber feet of most of my Woodstocks have turned into something like chewing gum over the years. Which means that they will be destroyed when the screws underneath need to be accessed. Has anyone come up with something to replace those feet with?

I can say that not a single rubber foot of my (Non-Woodstock) HP calculators has detoriated this way. They simply didn't have a chance: most of them came off and have been lost. I don't know why this happened, but this was the fate of all my HP41s. Years ago a friend gave me two 41CVs, both with intact feet and obviously used for 10 or 20 years, but within a year or so they most of their rubber feet first came loose (it looked like they had become slightly bigger) and finally they popped off.

What about rubber adhesive strips? Could this be a suitable replacement? Is a special brand or type recommended?

Dieter

[badaze]

I used double sided adhesive tape (Scotch brand) and it worked well.

[Dieter]

(01-07-2018 12:27 PM)badaze Wrote:  I used double sided adhesive tape (Scotch brand) and it worked well.

Thank you. But Scotch is specialized in adhesives, so I assume there are dozens of different adhesive tapes. ;-) Which one exactly do you recommend?
And what kind of rubber? Most of my 41's feet are lost.

Dieter

[badaze]

Well. I bought the tape at the supermarket so I think it’s the standard one.

[hewlpac]

Scotch poster tape is post it adhesive. Easy to remove and reposition without chemicals.

[Dave Frederickson]

(01-07-2018 09:41 AM)Dieter Wrote:  I don't know why this happened, but this was the fate of all my HP41s. Years ago a friend gave me two 41CVs, both with intact feet and obviously used for 10 or 20 years, but within a year or so they most of their rubber feet first came loose (it looked like they had become slightly bigger) and finally they popped off.

What about rubber adhesive strips? Could this be a suitable replacement? Is a special brand or type recommended?

Dieter

Replacement feet for the Voyagers, 41/71, and 75 can be found on eBay and at Samson Cables.

The Woodstocks, on the other hand, have feet that are inserted into the screw holes on the bottom of the calculator. Mine have started to turn gooey as well.

Dave

[rprosperi]

(01-08-2018 08:53 PM)Dave Frederickson Wrote:  Replacement feet for the Voyagers, 41/71, and 75 can be found on eBay and at Samson Cables.

The Woodstocks, on the other hand, have feet that are inserted into the screw holes on the bottom of the calculator. Mine have started to turn gooey as well.

Dave

The best substitute I've found for Woodstock feet is amazingly cheap, plentiful and easily available, and even come in multiple colors. Cut up a block eraser and insert it into the feet wells. I don't have the dimensions written, I just took an old one as a guide and then with an X-Acto knife, cut some similar sized replacements out of the eraser. Total cost is not quite free, but darned close.

If you've not removed Woodstock feet, pull the old feet out to verify size before you cut; they are 'deeper' than they appear, and it's natural to make new ones that are too short if you haven't checked.

Buy 2 erasers when you find the right color/material, even though 1 will generally be enough material for 2 sets of 4 feet. As erasers they will (slowly) wear down over time, but then you'll have a spare ready to go.

It needs to be said: use white colored erasers (or putty if you can find it) as pink would juts look... well like an eraser.

Edit: Some samples, just to be clear what type I used:

Plain

Fancy Oooo... Polymer

[Harald]

Ok, here is an update and a question.

I decided on an HP25 keyboard after realising that actually both, the ON/OFF and PRGM/RUN switch make sense.
The main PCB I used came from a very dead 25c, on the plus side the PSU on this was on a seperate board and could be completely removed. On the negative side, the anode and cathode driver spacing was wrong. This is a very late 25C.
After realising that the LED display would sit too high if I used the low profile sockets (does this work for others?) I decided on soldering the LP pcb directly to the calculator PCB.
After assembly the calculator powered right up and everything looked fine. Then I installed the GPS module and PSU for it and reassembled the calculator. I could turn on GPS, but after a second or so it would turn off automatically. So I opened the calculator in order to measure the power on signal for the GPS-PSU. Hooked up a scope probe and turned on the calculator. But ever since doing that, any key press results in a "0" on the display. Effectively all keys are interpreted as the "0" key. What have I done? Have I shorted something? I am a bit lost now.

Cheers,
Harald
Edit: It is still only the "divide" key that gets the calculator back out of sleep mode. I guess that means the PIC is dead...

[PANAMATIK]

(01-09-2018 09:39 AM)Harald Wrote:  Edit: It is still only the "divide" key that gets the calculator back out of sleep mode. I guess that means the PIC is dead...

"divide" key is meant to wake up. Other keys don't wake up. This is normal to minimize accidentally wake up when carrying the calculator inside the pouch. GPS module needs more current and I observed, that low batteries will reset the circuit when GPS is switched ON. Perhaps you just have to recharge the batteries. Did you measure the /SHDL signal at the Power supply. If it is always high and battery is low this could explain the behavior.

Bernhard