Hi Ok, what else is on the same board as the front end?
Is this a “chop a big hole in the board” project or is it a more elegant, replace the whole board approach. If you are just going to chop a hole in the board, what else buried in there. There is way more to this than just an input circuit. Bob > On Jan 27, 2016, at 3:38 PM, Bruce Griffiths <bruce.griffi...@xtra.co.nz> > wrote: > > Something like the attached schematic should suffice however an extra gain > stage would probably be necessary to achieve the 100mV sensitivity.NB Vcc = > 15V, Vee = -15V. > Bruce > > > On Thursday, 28 January 2016 5:02 AM, paul swed <paulsw...@gmail.com> > wrote: > > > Some great comments and like all of you I like my 5370s and 5345s. Real > buttons no mouse. Must be a throw back to the dark ages. > Always knew about the fan issue on the 5370 and have added fans to my main > operating unit. > But it had not occurred to me that the way the front panel is laid out > there may be little actual airflow across those chips. Thats quite a > thought. > So for those with working units that may be a completely seperate thread. > How hot do they get? Then some solution for that. > Essentially fix it before it dies. > Then there is the question I posed. > Skipping all of the details like adjustable slicing polarity and such. What > is the minimum to get a signal into the counter as a way to return it to > some usable service and certainly verify the bad frontend. Lets call this a > poor but useful answer. > From that point it returns to this discussion. > But a full new front panel. As Perry says most likely not. > I do have 2 X5345s that I am pretty sure I need to dive into the front end > on. My excuse other projects... > Regards > Paul > WB8TSL > > On Wed, Jan 27, 2016 at 7:46 AM, Bob Camp <kb...@n1k.org> wrote: > >> Hi >> >> Ok, well let’s put some dimensions on it. >> >> Say that the new board for the counter costs $400 each. (and that’s >> probably low). How many are people likely to buy? >> >> If so how much would you pay for a working 5370? >> >> Bob >> >> >>> On Jan 26, 2016, at 11:08 PM, Perry Sandeen via time-nuts < >> time-nuts@febo.com> wrote: >>> >>> Hi, >>> Wrote: Since the front end chips are mixed signal ASIC’s, it will take >> more than a bit of time to replace them directly. Re-doing the entire front >> panel board is the most likely way to “fix”the problem. The question is - >> why do that at all? Just do a PC instrument that does the same thing as the >> counter with way less effort….. >>> Well, I have two reasons not to. >>> First I have about $1800 invested in my 3 5370’s including the new CPU >> boards and blowing that off is not in my budget. I’ll kludge the living >> daylights out of my units before blowing off my investment. >>> Second, I haven’t the slightest clue on how to do a PC instrument and I >> have to many other projects to finish to learn something new. >>> Also there was much discussion about A and B cooling in the past and it >> seems the only things some did to their units was the addition of fan(s) on >> the cooling fins. I had an external fan on a B I was running and the thing >> still was too hot. >>> IMNSHO, I believe the front end chip failure is aggravated by the high >> interior heat level. I’m committed to a number of other projects so it >> will be a while before I can work on mine. >>> I’ll either rip the whole PS out and put it on another chassis, try >> better 3 terminal regulators instead of the installed pass transistors, >> install switching regulator PS’s in place of the original PS, cut holes in >> the top lid and install 10 or 12 computer fans. Or a combination of the >> afore mentioned. >>> I don’t give a rat’s behind how it will look. I’m only interested in it >> working properly. I’ve spent 50 years in the electronics industry and I >> will find a way to skin this cat. I’ve done this to other equipment before. >> And when done I’ll tell the list how I did it. >>> Regards, >>> Perrier >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > <5370FrontEnd.PNG>_______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.