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If you wish to place an order for a genuine CES 510SA MK3870 microprocessor, please so as to coordinate your order. The selling price for each is USD$20 + $5 s/h (or send your best offer). We do accept secure credit card payments and Paypal.

Brief history of the CES 510SA Smart Patch

During the 80's and 90's it was already possible to place phone calls from a car equipped with just a 2-way radio, or even on foot with a portable radio, being the only condition that they where equipped with a DTMF keypad. You only needed to have a piece of equipment known as the CES 510SA Autopatch, better known as "Smart Patch". When hooked up to a VHF or UHF base radio, and simultaneously to a conventional telephone line, it would enable anyone to remotely place and receive telephone calls in simplex mode, or with a few modifications you could hook up the 510SA to a repeater which would enable you to place half-duplex telephone calls. The use of these type of systems proliferated to such degree in some Latin-American countries, and even in the US, that the factory had to speed up production in order to be able to keep up with raising demand.

The CES 510SA Smart Patch can be considered as one of the most popular and successful telecommunications products, but with the arrival of modern cellular technology during the early-mid 90's many autopatch systems where abandoned in favor of the new more modern technologies. But to this day, around the globe there are still thousands of autopatch systems still in operation, and in spite of its inherent limitations they still posses some advantages over cellular phones: the calls placed through an autopatch have a much lower cost because they are routed through a conventional land line, and the system can also be used in the same manner with internal PABX extension lines, and in this way facilitate remote access to internal private lines and extensions without having to go through the commercial telephone system. In other words: calls that are practically free.

The 510SA autopatch was sold extensively by CES from 1987 to about 1992. During the whole production period of the Smart Patch, CES incorporated small changes and updates to the initial design in order to integrate some improvements or correct initial design mistakes. The various production version where identified with a letter printed on the main circuit board, being "A" the first version. Subsequently revised versions where released identified as B, C, D ... until approximately letter H, which possibly corresponds to the last production run.

Our Stock

We have for sale a very limited stock (< 20 pcs.) of MK3870 microprocessors (also known as U3870, or MK38U70), which where used in the CES 510SA Smart Patch. This IC in particular, while being in general terms a generic microprocessor, does in fact contain the specific internal programming for this application, and is therefore the heart of the 510SA autopatch as it controls all of its functions. It is identified as U12 in the schematic of the 510SA autopatch.

The MK3870 which is offered here corresponds to one of the more modern later production runs (F, G, o H) of the 510SA Smart Patch, but we are unsure as to which one it exactly corresponds. In any event our MK3870 microprocessor should be plug-in compatible without the need for any modifications with most of the existing modern production versions, but it may still be possible that some minor modifications could be needed in order to reap maximum benefits from it if used in the initial older versions of the 510SA. These modifications and updates would in any case also have a side benefit of updating the specifications and features of any 510SA to a much more modern version. The schematic and parts layout of the 510SA available at the CES Website should correspond to one of the later production versions, and could be used as a reference in order to determine if any modifications or updates will be necessary before our MK3870 microprocessor is used.

If you are among the many still faithful autopatch users or owners, but your CES 510SA Smart Patch has a damaged microprocessor (which was a common occurrence due to lightning strike or voltage spikes at repeater sites), this is your chance to bring it back to operational status. Even if your 510SA is currently operational, it is still very recommendable to get a spare MK3870 microprocessor for any future needs. The selling price of each is USD$20 + $5 s/h (or send your best offer), and you can to place your order. We are able to securely accept any credit card payment and Paypal.

All our MK3870 microprocessors are still stored in their original antistatic carrier tubes, and where never used or even removed (other then to take a few pictures), condition known as NOS, or New Old Stock. It is worthwhile to mention that this part is no longer available, not even through the original autopatch manufacturer (CES) as their stock ran out somewhere around 1996, so this might be your very last chance to buy an absolutely brand new and original MK3870 specifically manufactured and internally programmed (ROM memory) to be used in a CES 510SA Smart Patch.

Note: even though our MK3870 microprocessors are labeled as "M3872GTB1", we guarantee they are 100% original parts as these where ordered back then directly from the factory as CES 510SA Smart Patch spares. Furthermore, on one of the antistatic carrier tubes there is still a identification label that clearly reads "U3870 20 pcs", which was one of the numbers used to identify the CES 510SA Smart Patch microprocessor.

You can view more information about programming and schematics of the CES 510 SA Smart Patch at the CES Website.

If you wish to place an order for a genuine CES 510SA MK3870 microprocessor, please so as to coordinate your order. The selling price for each is USD$20 + $5 s/h (or send your best offer). We do accept secure credit card payments and Paypal.