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Rob <nomail@example.com>: May 16 05:44PM > Basically my question is if the usb-prl converter works both ways.   > Or how do I know if it does.   Ok so that has been answered: It doesn't.

Stephen Wolstenholme <steve@easynn.com>: May 16 01:04PM +0100 On Fri, 14 May 2021 09:56:16 +0000 (UTC),   >If I have a converter between a USB computer and a parallel printer, will it >also work between a usb printer and parallel computer?   >(I want to replace 1995 printer which is connected to 1995 and 2007 computers.)   You probably won't need a converter as will almost certainly be USB to USB.   Steve   -- http://www.npsnn.com

Jason <jayson1@stiger.com>: May 17 07:10PM -0400 I just picked up a small spectrum analyzer to check out some transceivers I have. They are 10 meter ham units and put out anywhere from 4-12 watts @ 50 ohms. The new spectrum analyzer can handle a maximum of 10 dbm. What size voltage divider would I need to reduce the transceiver wattage to less than the 10 dbm for the analyzer? Thanks.

T i m <news@spaced.me.uk>: May 23 07:20PM +0100 On Sat, 22 May 2021 18:07:17 -0700 (PDT), whit3rd <whit3rd@gmail.com> wrote:     >They almost always fail with a dead short, couldn't miss that with >a diode check ( 0.2 to 0.8V is a typical good-rectifier reading forward, >and no conduction in reverse).   Agreed. I think I read .2xxV on my DMM diode test in the forward (x2) and as you say nothing in the reverse (x2 + 2 (between the two outers)).   >> FWIW I measure about 10V DC on the output (no load) and only about .5V >> on the AC range   >Since the capacitors on output were replaced, are you sure they're low-ESR types?   I believe they were:   "Panasonic 1000uf 16v Electrolytic Capacitor 105 LOW ESR FR Series EEUFR1C102L" ?   https://industrial.panasonic.com/ww/products/capacitors/aluminum-capacitors/aluminum-cap-lead/models/EEUFR1C102L   >The ripple current ratings have to add up to about the output (20A) of the unit. >Correct capacitance but low ripple current ratings (aka high ESR) on the replacements >could explain bad output with good rectifier.   (Interesting, thanks) From that spec the only value I can see related to ripple is:   "Rated ripple current-1 (mA) 1560.0"   So the 4 would give 6.24A but would that still impact the off load voltage?   I might see if I can rig up my USB scope and actually 'see' what the output is doing.   Cheers, T i m   p.s. Because I need the 3D printer running I've since bought 2 x Mean Well (SP-200-12) 12V x 16.5A PSUs and have tacked them in to be able to get going (and need to design and print some new mounting brackets <g>). However, whilst it looks like I could end up spending ~10 GBP (more if you count to total cost when it's more sensible to buy 10 off something when I only need one) to get this old PSU running (assuming I ever do etc) and could buy another cheap one new for just a few pounds more, I am interested to see if I can get it going (with the guidance of some good folk here etc <g>), firstly, because I would find it satisfying, second because I then have a spare PSU and third I wouldn't them have to throw the rest away. ;-)

T i m <news@spaced.me.uk>: May 17 09:22PM +0100 On Mon, 17 May 2021 11:00:05 -0400, legg <legg@nospam.magma.ca> wrote:   <snip>   >Check big primary bulk electros - voltages should be roughly >equal with small low-frequency ripple.   166V across each, no real measurable ripple (off load of course).   Cheers, T i m

whit3rd <whit3rd@gmail.com>: May 23 10:20AM -0700 On Thursday, May 20, 2021 at 8:44:37 AM UTC-7, John Crane wrote:   > ... I'm sure there has to be some company that can custom > manufacture crystals to specs. I did try Bomar, but have not received a > reply.   There's factory-programmable oscillators that use internal logic to create custom frequencies, which has better cost and leadtime than custom crystals.   DigiKey will even program it for you...   <https://www.digikey.com/en/products/detail/epson/SG-8018CB-TJHSC/7784073>

Ralph Mowery <rmowery42@charter.net>: May 23 01:27PM -0400 In article <f05cb46b-1214-42fc-8bf8-933d5fdd4835n@googlegroups.com>, whit3rd@gmail.com says... > custom frequencies, which has better cost and leadtime than custom crystals.   > DigiKey will even program it for you...   > <https://www.digikey.com/en/products/detail/epson/SG-8018CB-TJHSC/7784073>   I bought a couple similar to those. Problem is that if you want to put them very close on frequency like you can with a crystal and trimmer capacitor you are out of luck.   They only cost a few dollars, under $ 5 if I recall correctly instead of around $ 50 that Bomar would want for a crystal. They do put out a waveform roughly equal to a square wave.

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