HP 15CLE - how successful?

[axd1967]

Was wondering how successful this model has been; in other words, would there be yet another batch be produced? (With some bugs corrected, preferrably...)

[Thomas Radtke]

While it was still in production, street prices were increasing, starting from less than $90 for which I got one from SC. My conclusion is the 15C LE was a success, and it makes me wonder why there was no regular edition.

We recently learned the SoC which several calculators including the 15C LE are based on are out of production, so chances for a new edition of this wonderful calculator are probably approaching zero.

[Katie Wasserman]

(09-25-2014 09:27 PM)Thomas Radtke Wrote:  We recently learned the SoC which several calculators including the 15C LE are based on are out of production, so chances for a new edition of this wonderful calculator are probably approaching zero.

I'm not so sure. The latest model 12C uses the same AT91SAM7L128 chip. Since the 12C is HP's best selling calculator (by far) they're going to have to come up with an alternative chip if they want to keep making those. Whatever alternative them come up with will be a suitable candidate for the 15C too.

[David Hayden]

(09-25-2014 05:06 PM)axd1967 Wrote:  Was wondering how successful this model has been

I suspect that they ran two manufacturing batches of 10,000. As I recall the LE numbers were all less than 10k and stocks started drying up. Prices climbed. Then suddenly vendors had them again and the LE numbers were higher. Two batches would explain this.

Tim did mention something else about it at HHC but that may have been under the NDA.

[Thomas Radtke]

David, IIRC there were (somehow different?) US and non-US models, where the latter came out quite late. That might explain your observation.

[ElectroDuende]

I've just received a call from the girl at reception desk while reading the forum... my new, unused, 15C LE has just been brougth by the postman.

:-)

That makes my... 7th HP. My wife should start to worry, I'm afraid.

For the interest of the forum, serial number is 130xx

[Tim Wessman]

Mine has a "limted edition" number of "42". :-D

[Dave Frederickson]

(09-26-2014 11:21 AM)David Hayden Wrote:  I suspect that they ran two manufacturing batches of 10,000.

I think there may have been more batches. A buddy at work bought one out of the first batch from SC for something like $150. Sometime after that HP had new stock and I bought mine off the HP website for $99 including shipping. Then I started seeing LE's on eBay being advertised as not having the wobbly shift key issue. So were there at least three batches?

Dave

[Jose Gonzalez Divasson]

Last 15c LE that I have seen had a serial number over 23000...so my guess is 25000 total.

[d b]

(09-27-2014 08:40 PM)Jose Gonzalez Divasson Wrote:  Last 15c LE that I have seen had a serial number over 23000...so my guess is 25000 total.

Jose; So yours - or the guess of 30000 (3 batches of 10000) are valid. HP has customarily kept a sizeable number back in each model for warranty replacement too. If you need another one, check back in ten years after they go off sale. Mine is # 303, so i can't add any more to the top end conjecture.

[robert rozee]

the problem with the 15C LE (and other recent models) is that they are built with technology that does not have durability over an extended period of time. lead-free solder, conductive adhesives, all lead to an expected failure within 10 years. and whereas the original 15C had ICs built specifically to last an extremely long time, the modern chips are very much consumer grade.

while the 15C LE and current-generation 12C calculators make perfectly fine 'daily use' machines, neither are of a 'collectable' grade. it is like having a treasured collection of icecubes.

rob :-)

[walter b]

(09-28-2014 08:21 AM)robert rozee Wrote:  it is like having a treasured collection of icecubes.

Nice comparison

I wonder if companies making airplane or military products are soldering lead-free as well. If not, why not? (Hope that question doesn't bring me in conflict with arbitrary forum laws.)

d:-?

[axd1967]

(09-28-2014 08:21 AM)robert rozee Wrote:  the problem with the 15C LE (and other recent models) is that they are built with technology that does not have durability over an extended period of time. lead-free solder, conductive adhesives, all lead to an expected failure within 10 years. and whereas the original 15C had ICs built specifically to last an extremely long time, the modern chips are very much consumer grade.

while the 15C LE and current-generation 12C calculators make perfectly fine 'daily use' machines, neither are of a 'collectable' grade. it is like having a treasured collection of icecubes.

rob :-)

Speaking of obsolescence... A rare glitch in time?

[Daniel Kekez]

(09-28-2014 09:15 AM)walter b Wrote:  I wonder if companies making airplane or military products are soldering lead-free as well. If not, why not?

Military and aerospace products are exempt from the Reduction of Hazardous Substances (RoHS) directives that require consumer products to use lead-free solder. Some countries have also exempted medical and telecommunications infrastructure from the requirement. When building high-reliability products, there is a reluctance to introduce changes in the manufacturing process when there is the risk failures that might not be apparent until years after delivery.

One failure mode is tin whiskers that can grow on lead-free solder joints. These are small tin hairs or tendrils that form over time on lead-free joints in the presence of mechanical stress, leading to short circuits. NASA Goddard Space Flight Centre has an extensive site dedicated to tin and other metal whiskers.

[walter b]

Daniel, thankyou for the information. Would be interesting to find out whether scientific instruments fall under the same regulation. Serious scientific instruments in particular are no consumer products IMHO.

d:-)

[ElectroDuende]

(09-29-2014 02:20 AM)Daniel Kekez Wrote:  Military and aerospace products are exempt from the Reduction of Hazardous Substances (RoHS) directives that require consumer products to use lead-free solder. Some countries have also exempted medical and telecommunications infrastructure from the requirement. When building high-reliability products, there is a reluctance to introduce changes in the manufacturing process when there is the risk failures that might not be apparent until years after delivery.

The information regarding the Tin Whiskers is very interesting; I had never heard about that.

Regarding the RoHS adoption, we had many problems in the company where I work. We source electronic boards from a handful of providers and, during the initial weeks, our return rate sky-rocketed. Some of them even tried to cheat us using lead when they shouldnt.... even now, several years after that, we still have a (moderately) greater rate of return due to soldering problems...

[jebem]

(09-29-2014 02:20 AM)Daniel Kekez Wrote:  One failure mode is tin whiskers that can grow on lead-free solder joints. These are small tin hairs or tendrils that form over time on lead-free joints in the presence of mechanical stress, leading to short circuits. NASA Goddard Space Flight Centre has an extensive site dedicated to tin and other metal whiskers.

Tell me about it!
Just for fun, I used to open the damaged germanium AF radio-frequency transistor series (the shielded ones having 4-pin, one being the shield pin connected to the metal case) removed from old transistor radios from the 60's, just to find out what was the cause of failure - The metal wires from pnp junctions had grown metalic "hairs" touching the case.
This is a classic cause for failure on old Ge transistors.

[Thomas Radtke]

We'll see. In three Years the lead-free 35s will be 10yo! Thus far, my sample works.

And maybe, when the last 15C LE gave up the ghost, someone will offer a replacement PCB, just like e.g. the Amiga Phoenix. It gets easier to develop and produce drop-ins like these all the time. That's why I still own a dead 25 or a Gossen CdS meter :-).

[Jim Horn]

As mentioned by others, aerospace and military still used lead/tin solder. While most vendors only supply ROHS parts anymore, they can be soldered with lead/tin as long as the temperature profile is controlled properly, a skill any decent assembly house has today. In my work at Wescam, Insitu, and United Technology Aerospace Systems (cloudcaptech.com), classic lead/tin eutectic solder has been the norm.

The tin whisker problem has been mostly tamed by careful selection of solder alloys, temperature profiles, proper conformal coatings and other tricks. But we're still not quite there yet. The greater brittleness of lead-free solder joints has also caused concerns in high vibration and temperature cycling cases such as ours. An example of failure of that last is many laptop computers have failed due to temperature cycling fracturing solder joints of their tiny QFN package power supply ICs (I've replaced same several times).

Fortunately, our calculators aren't subject to the high power and related stresses so should do pretty well. We'll see...