Beautiful work Paul! On Friday, 25 June 2021 at 18:10:25 UTC+10 Paul Parry wrote:
> Hi Alex, > > The electronics were custom designed, and one of the members of this group > kindly did the PCB layout / design. There was an analogue processing board > that had 2 channels ( 10 pictured, so 20 channels ) That contained a > butterworth filter for selecting the desired frequency band, you can see at > the bottom of the board the relevant components are fitted, as they > determine the frequency so during test and setup they get fitted. The rest > of the circuitry linearizes the signal and then some circuitry to drive the > IN-13. > > There is then another board that isolates and amplifies the incoming > audio, and provides the 120v dc for the tubes. > > [image: IMG_20171115_1216430.jpg] > > Here's a view of the complete set up inside the case: > > [image: IMG_20180802_150246.jpg] > > They are quite a job to put together, as I only made them in small > quantities, the boards were all SMT assembled by hand which took a good 30 > hrs to build up a set up, and then each channel had to be individually > 'tuned' so you need a calibrated signal generator and a scope, but as it is > all analogue you end up with an instantaneous response and the selectivity > of the channel is very precise. > > Best wishes, > Paul > > > On Thursday, 24 June 2021 at 09:31:44 UTC+1 Alex wrote: > >> Hi Paul, >> >> Can I ask what electronics you used for these? Was it completely custom >> or something bought in? I know I have a case of in13 somewhere (and many >> cases of in9) so should plan something with them and this looks very nice! >> >> Cheers, Alex >> >> >>>> >>>> >>>> >>>> -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/e299a02f-3f0f-4685-918c-65d704793c60n%40googlegroups.com.
