Yes the Zenner was intended for ESD protection, I was thinking of a 6.8V one when using 3xAA battery pack. Select one with low leakage current @ 5V (a 3xAA would output no more than 5.2V when fresh).

True. How about this: https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/574096951 https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/574096951 ---In TekScopes@..., <davi

Check Mouser part 534-2487 I think it's perfect. Alternatively you could try a 4 AA holder and use a 7805 as David suggested. ---In TekScopes@..., <vdonisa@...> wrote : I don't think one c

I don't think one could predict what the IC will do. It's your call :-) I would first check if there's any compassionate list member living in your area to provide a plan B (i.e. help with calibration

One more thing.... the standby (low) current of the memory IC will happen only when all control signals are inactive (WE, OW, CE1, CE2). If one of them is active, then the chip could draw more current

Mhh... Assuming that it's the memory IC at fault, the question is - will it get worse and eventually completely fail over time? Or will it stay stable at 170uA draw with no foreseeable failure? If you

There's also a R2530 of 10MOhm somewhere, used to monitor the battery voltage, I would check that one too before blaming U2460. ---In TekScopes@..., <steve65@...> wrote : I removed CR2371,

The 173uA current seems high. According to the datasheet, the battery has a capacity of 750mAh. Also the diagram indicate that at 10uA it would last about 50000 hours. Which means that at 100uA you wo

As we're speaking Mouser has about 1300 Central Semi MPSH10's in stock. If you prefer the ON Semi MPSH10G version Digikey has some 7000 of them. ---In TekScopes@..., <daviddigiacomo@...> w

Panasonic look for FR or FM United Chemicon look for KZE and KZM Nichicon HE and HW should work too Cap that are very close to some hot heatsink you may also look at specialty stuff like Nichicon BT,

How would you approach this one: http://www.xkcd.com/730/ ---In TekScopes@..., <davidwhess@...> wrote : I usually find that anything SPICE simulates accurately, I can just figure out with

Not only that but they also added photos of them in the gallery. But why oh why would someone use "Search Conversations". ---In TekScopes@..., <kc0wjn@...> wrote : I thought some time back

Remove the power cord :-) Now seriously. You'll need to loosen/remove the screws holding the scope's back chassis plate. That will make extraction way easier. ---In TekScopes@..., <snmp_4u

This is from my 2467B: https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/1079293848/lightbox/925121236 where indeed they use a NEC D4364C-15LL for U2460 and no U2560 installed. From the data

P.S. Correction - the capacitor can discharge lower than 3.6V; so at power on it will charge from whatever it managed to reach up to +5V P.P.S. Interesting reading - the datasheet of the Maxim DS1210.

The only logical explanation I see (other than the circuit being iteratively "refined" as you suggested in a previous post) is that they were trying to limit the speed of the voltage variation at RAM'

Looks to me like the purpose of Q2270 is to take over the current load through CR2370/CR2370 while we have +5V and normal operation, offering a low Z power supply compared to just the diodes. While th

It could be that the purpose of that whole circuitry is to disable writing to the RAM chips (via the CE signal) when an impeding power-off is detected (you don't want to allow the processor to continu

If U800 is good and scope is working, one will face the following dilemma: - using a glued heatsink means using a layer of thermally conductive epoxy, which ain't really that conductive, and if you st

Yes, several mental disorders ranging from anxiety to PTSD. ---In TekScopes@..., <snmp_4u@...> wrote : another question I have: if this chip ever does fail on me, will it cause downstream