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Massjmo72 · (This post was last modified: 10-01-2018 09:34 PM by Massjmo72.)

Hi everybody, I just registered to the forum but have been lurking on the incredible database that MoHPC is for the past 12 years or so.
I'm in the process of acquiring a SS HP-01 in very good condition and I am a bit concerned about the gaskets. I couldn't find any reference online on the size and brand suitable for a replacement. Also, it seems in need of some cosmetic work done, does anybody know of somebody that does this kind of work here in the US?
thank you all for your help
Massimo

**rprosperi** · 09-24-2018, 01:14 AM

(09-23-2018 06:50 PM)Massjmo72 Wrote: Hi everybody, I just registered to the forum but have been lurking on the incredible database that MoHPC is for the past12 years or so.
I'm in the process of acquiring a SS HP-01 in very good condition and I am a bit concerned about the gaskets. I couldn't find any reference online on the size and brand suitable for a replacement. Also, it seems in need of some cosmetic work done, does anybody know of somebody that does this kind of work here in the US?
thank you all for your help
Massimo

First, welcome to the MoHPC Forums! Seems you're familiar, so just join right in....

Second - suggest you post this (another copy is fine) in the Main Forum. It's appropriate for there, and many more people will see it there, so you stand a better chance of getting useful replies.

Good luck with your HP-01, and please record your steps and success as you proceed .

Massjmo72 · 09-24-2018, 01:25 AM

Thank you for the welcome.
So far I bought a non-working SS HP-01. The guy said that it was stored for decades without the batteries. I did buy it to keep it as a donor for the other one I'm still bartering for. Another positive note is that the "not working one" comes with the original user manual and stylus. As soon as I get it I'll try fresh batteries and, if it works, I will have 2. In the worst case scenario I will have enough spare parts to keep the other one going.

Harald · 09-24-2018, 07:43 AM

(09-24-2018 01:25 AM)Massjmo72 Wrote: Thank you for the welcome.
So far I bought a non-working SS HP-01. The guy said that it was stored for decades without the batteries. I did buy it to keep it as a donor for the other one I'm still bartering for. Another positive note is that the "not working one" comes with the original user manual and stylus. As soon as I get it I'll try fresh batteries and, if it works, I will have 2. In the worst case scenario I will have enough spare parts to keep the other one going.

Also, if it doesn't work, have a look at http://www.panamatik.de
Bernhard has designed a replacement PCB for the HP01 and as long as the LED display is fine, he can repair it.

Massjmo72 · (This post was last modified: 10-02-2018 06:54 PM by Massjmo72.)

I spoke to the previous owner and he said that it was stored without batteries for decades. Hopefully there are good chances it has a working module. The other option from the gentleman in Germany is great to bring an HP-01 back to life. That would leave the cosmetic restoration still to be addressed.
Thank you

Thomas Klemm · 09-24-2018, 02:19 PM

(09-23-2018 06:50 PM)Massjmo72 Wrote: Also, it seems in need of some cosmetic work done, does anybody know of somebody that does this kind of work here in the US?

I just know of the amazing work done by Geoff Quickfall.
But he's located in Vancouver, Canada.

The mentioned link appears to be broken. However this one works.

HTH
Thomas

Massjmo72 · 09-24-2018, 02:46 PM

Thank you Thomas! That's what I was looking for.
Geoff Quickfall does an amazing job! Is he a member of this forum too?
As soon as I get the first HP-01 I'll take high-res pictures and post them. The "broken one" doesn't seem to have too much wear. I am planning on wearing one of the two on special occasions and leave the other one as "safe queen".
Again, thank you all for the precious help.

Thomas Klemm · 09-24-2018, 03:23 PM

(09-24-2018 02:46 PM)Massjmo72 Wrote: Is he a member of this forum too?

Yes, I've linked his name to his profile page. From there you can either send him an email or a private message.

Best regards
Thomas

Massjmo72 · (This post was last modified: 10-02-2018 06:55 PM by Massjmo72.)

I have two SS HP-01 coming, one is a full set. I'll post pictures as soon as I get them.

Massjmo72 · (This post was last modified: 10-01-2018 09:27 PM by Massjmo72.)

So, the first one has arrived...

Massjmo72 · (This post was last modified: 10-01-2018 09:27 PM by Massjmo72.)

Here some pictures of the full set. It comes with foam inserts and besides all the original paperwork it has the original receipt of sale from HP being an employee purchase, registration receipt and HP service center letter from 12/20/79 were it states that the module was changed. Serial number is low, being 00231 and production code 1912A. The watch is running 2 minutes behind, I don't know if it's because it needs fresh batteries or some oxidation. It looks very good cosmetically, I would rate it at 8.75/10 and the extra papers from the original owner are bonus.

Massjmo72 · (This post was last modified: 10-01-2018 10:37 PM by Massjmo72.)

Any idea on what the possible cause of the module running behind could be?
Overall I love the design, the weight and feel of the watch on the wrist, it's just perfect. It feels something substantial worth the money spent for it.
Any insight is greatly appreciated
thank you

Geoff Quickfall · (This post was last modified: 10-02-2018 06:00 PM by Geoff Quickfall.)

Pm sent

HP used a 38.4 kHz crystal cut to vibrate at that frequency. They then timed it to 30 seconds a year. It is temperature sensitive though. Also, as it ages it will drift. Prior to failure, and some do fail, they drift rather a lot.

HP included a trimming capacitor which can fine tune the watch frequency. The trimming capacitor is also temperature sensitive. Do not attempt to change the trimming capacitor factory setting. These age and become brittle.

You say 2 minutes drift, over what period of time? What are you using as a base reference for time?

The watch looks spectacular.

Now if the 2 minutes (a day) is annoying enough then securing a 38.4 kHz crystal for replacement becomes problematic, unless someone out there has a source other then dead modules. If too annoying then I suggest a PANAMATIK module and harvesting the LED display as a donor. Keep the old module as it is functional.

teenix · 10-03-2018, 08:35 AM

There are miniature crystals available (Mouser for example), but they may not be a suitable replacement.

It is also possible that the trimmer capacitor has deteriorated so that its capacitance is outside useable limits, and will also need replacing.

In either case, a delicate operation.

cheers

Tony

Massjmo72 · 10-03-2018, 10:59 AM

Thank you for the replies. I monitored the watch over a 24 hr time period. As base reference I use my iPhone clock. I set the time on the HP-01 and check it 30 minutes later and it's 2 minutes behind.
In other words the module is toast. That's a bummer.
I'll wait to get the other one and see what's wrong with it. Maybe between the 2 I can have a perfect one with spares to keep it going.

Massjmo72 · (This post was last modified: 10-03-2018 07:03 PM by Massjmo72.)

Yesterday, on a whim, I changed batteries and with a set of fresh ones I synchronized the watch down to the second with my iPhone and 14 hrs later it's still spot on and keeping time accurately. I'll keep checking on it for the next 34 hrs and see if there's any variation.

I had to remove the watch and all the content from the leatherette case because it started braking down light-speed fast. It was sticking to my fingers and to the cardboard box. Too bad there isn't a way to stabilize the synthetic material.

Massjmo72 · 10-04-2018, 02:20 PM

The second HP-01 has arrived. (the one on the left in the picture with his brother) Cosmetic condition is even better than the other one.
The crystal is almost pristine (except for my fingerprint in the picture). The keyboard plate is almost perfect just few keys have rotated possibly a sign that somebody tried to fix it at some point. I'm expecting a shipment of batteries so I can test it.
Eventually, if Geoff Q. is available, I will send them to him for a cleanup and cosmetic treatment.
The first one is still running accurate with no minutes loss anymore.

burkhard · 10-04-2018, 02:54 PM

Looking at the picture of the HP-01, I suddenly realized that it isn't RPN. I had for years just assumed being HP from the 1970s, it had to be RPN. Weird.

This is actually a pleasant relief to me, as I will feel a little less "compelled" to buy one. :-)

I do like those old red bubble LEDs though.. fond memories I had of a cheap TI LED watch as a kid in the 1970s. The HP-01 is so much nicer though. If not for the cost, I'd have a handful, er.. armful!