Sennheiser Wireless 5000 Series PROMS

[Coop]

Hey All,

Since I am stuck at home with a leg cast and the parts for my other builds are not here yet, I was starting another project.
I do have some already really old Sennheiser Receivers and Transmitters. This stuff is still super nice to use and I don't want to throw it away. But I do have some units that need to be reprogrammed. Sennheiser is offering this at a ridiculous high price.
The transmitters use PROMS where the divider information for the PLL is stored. You just pop in a new PROM, do a little adjustment on the boards and you are ready to go. I do even have a software to calculate the files used for programming. The only problem is, that it uses N82S129 PROMS. Pretty old stuff that is hard to find and even harder to write to.

So I thought maybe someone here has experience with these PROMS and may be able to help.

Thanks in advance,
Johannes

 

[Jim McKeveny]

The Sennheiser 5000 Series was designed to be rebuilt and rebuilt again. (I had the pleasure of spending some time with Dr. Uwe Sattler, who was instrumental in the development). If you visit Live Audio Board's Wireless and Communication thread you will likely encounter some veteran Broadway RF types with intimate knowledge of how to reprogram the old SK's.

 

[Coop]

@Jim McKeveny Oh that is amazing.
Yeah, they are built to last ages. They are old but I still love to use them. Will need to check that thread out! Do you have link to that board?
Thanks for the info.

 

[Coop]

Thought I would give a little update.

I finally figured out how to reprogram an EM3032, EM3532 and an SKM3072. It was a bit of a challenge, but after reading several data sheets and how the whole PLL stuff works I came up with an excel sheet where the dividers are calculated and converted in the HEX numbers to be stored in the EEPROMs.
Next step will be burning som PROMs for the SK50s.

And I stumbled over a new problem. I do have some old L50 chargers for the batter packs used with SKM5000s and SK50s. They were originally designed to charge NiCd cells, but the new packs come with NiMh. There is a mod from Sennheiser to be able to charge the new packs. Does anyone have some knowledge what has to be changed?

 

[brock]

Hey Johannes, I also have a few EM3032, SKM5000 and SK50 that needs to be reprogrammed. Any way to PM you to maybe have your help on this thing? I really would like to use them again but without a little "update", it's really complicated because they all have different frequencies (coming from different second hand purchases).
Many thanks for your help!
Nicolas