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"Peter W." <peterwieck33@gmail.com>: May 03 10:01AM -0700 > Speaking of tools, does anyone know if the Plato 170 shear is still made in the U.S., or is it now Chinese?   https://www.techspray.com/5-ways-to-spot-a-counterfeit-tool-before-you-buy-it   The internet is your friend.   Peter Wieck Melrose Park. PA

"ohg...@gmail.com" <ohger1s@gmail.com>: May 03 12:06PM -0700 On Monday, May 3, 2021 at 1:01:46 PM UTC-4, Peter W. wrote: > > Speaking of tools, does anyone know if the Plato 170 shear is still made in the U.S., or is it now Chinese? > https://www.techspray.com/5-ways-to-spot-a-counterfeit-tool-before-you-buy-it   > The internet is your friend.   It is, but it doesn't always answer the question. That link doesn't either.

"Peter W." <peterwieck33@gmail.com>: May 04 08:24AM -0700 > It is, but it doesn't always answer the question. That link doesn't either.   THE TOOL IS SHIPPING FROM OUTSIDE THE US. If the cutter you have your eye on is coming from outside the US, be careful. That's not to say you can't or shouldn't buy our cutters from international sources. We sell all over the world to service the global marketplace. However, it is unlikely an authorized distributor would import cutters into their home country and ship them back to the US for an extremely low price.

"ohg...@gmail.com" <ohger1s@gmail.com>: May 04 09:22AM -0700 On Tuesday, May 4, 2021 at 11:24:41 AM UTC-4, Peter W. wrote: > > It is, but it doesn't always answer the question. That link doesn't either. > THE TOOL IS SHIPPING FROM OUTSIDE THE US. > If the cutter you have your eye on is coming from outside the US, be careful. That's not to say you can't or shouldn't buy our cutters from international sources. We sell all over the world to service the global marketplace. However, it is unlikely an authorized distributor would import cutters into their home country and ship them back to the US for an extremely low price.   That doesn't directly prove their origin. My old Plato cutters have a made in U.S.A printed in them. I haven't seen one picture of the new pliers that say this and no mention from the manufacturer that they still are (they used to advertise them as such). Where they're shipped from isn't proof. If Techspray gets a container of them from the Far East, they can get them into their distribution network just as easily and at less cost than they could likely make them.   I sent them an email and will report back when I get a reply.

"ohg...@gmail.com" <ohger1s@gmail.com>: May 04 07:22AM -0700 On Friday, April 30, 2021 at 11:56:37 PM UTC-4, Max D. wrote: > > > > ohg...@gmail.com <ohg...@gmail.com> wrote:   > > Which case style do you have? > Thanks for the offer. The old 1M30D-060 is a To-3PF, I believe, with the low profile upper half.   I went through everything I have including scrapped plasma sustain boards, and all the big plastic transistors I have are power mosfets. Sorry. What I would do is use DigiKey or Mouser's search parameter to select a suitable replacement.

"Peter W." <peterwieck33@gmail.com>: May 04 07:45AM -0700 On Thursday, June 12, 2008 at 11:51:40 PM UTC-4, Wilton Itamoto wrote: > cannot read the number on the case. Unfortunately I do not have another > inverter board on hand and Panasonic does not provide the schematic. > Anyone replaced one of these or know the part number?   There is always this - if you can find a data-sheet.   https://alltransistors.com/mosfet/   Peter Wieck Melrose Park, PA

Jason Bowers <jbbowersnospam@aol.com>: May 03 01:48PM -0400 On 5/3/21 10:04 AM, Ralph Mowery wrote: > ratio as I seldom need it and the scope I have now will calculate it and > put on the display. If your RMS meter shows abot 120 volts AC out of > the wall socket a scope will show around 170 volts peak.   Well, I've been using a coax T. On one end, there's the 50 ohm dummy load, other side is input from the URM 25 signal generator, and the final side goes into channel 1 of the scope. I wonder if I should use some sort of a buffer here, on the side leading to the scope, like a voltage divider, etc, rather than direct? Or, perhaps actually check from the "open circuit" output on the generator as the URM has that too? Yes, I'm now compensating for PP by converting to RMS after I see the waveform. It may be closer than it was, but will know with more certainty after the probes arrive today.   A small 1x 10x probe arrives today at last so I can at least check the scope's square wave output signal peg. See what happens then.   The frequency still seems to be showing higher than it actually is though. Even with a 30 Mhz scope like this, should I be able to "zoom" in to see just one or two waveforms? So far, I can't seem to get closer than 4-5 waveforms at 28 Mhz even with the 10x magnifier on.

Ralph Mowery <rmowery42@charter.net>: May 03 03:09PM -0400 In article <s6pd0p$hoc$1@dont-email.me>, jbbowersnospam@aol.com says... > Yes, I'm now compensating for PP by converting to RMS after I see the > waveform. It may be closer than it was, but will know with more > certainty after the probes arrive today.   Instead of the RF generator have you tried a transformer that converts the line voltage to something between 6 volts and 50 volts AC ? Then you can do the conversion from the RMS to peak voltage to see if the calibration is correct.   One other thing if it is a dual trace scope go to the X-Y mode and feed both chanels the same signal and see what the trace looks like.   As someone else mentioned feed the same signal to both inputs and use the invert function and see if they cancel each other out.   I am thinking that URM 25 has several matching networks that go on the end of the cable. Do you have the correct one for what you are trying to do ? Sometimes those networks get lost over the years.

Phil Allison <pallison49@gmail.com>: May 03 03:55PM -0700 Jason Bowers wrote:   ================== > though. Even with a 30 Mhz scope like this, should I be able to "zoom" > in to see just one or two waveforms? So far, I can't seem to get closer > than 4-5 waveforms at 28 Mhz even with the 10x magnifier on.   ** Completely normal.   28MHz is at the limit of the scope's range so no detail is visible on a sine wave. Also, the amplitude will by down by 30% or so from that at say 5MHz.   30 MHz scopes are are not "flat" to 30MHz but will be at least 3dB down.     ...... Phil

Jason Bowers <jbbowersnospam@aol.com>: May 04 05:59AM -0400 On 5/3/21 6:55 PM, Phil Allison wrote: > Also, the amplitude will by down by 30% or so from that at say 5MHz.   > 30 MHz scopes are are not "flat" to 30MHz but will be at least 3dB down.   > ...... Phil   Thank you and the others here! The scope seems fine. I was finally able to find out what happened to the square wave test peg. It dislodged during shipping. Reattached and a nice 2V PP 1 Khz square wave.   Phil, what you said was confirmed. If I input the signal generator and set for say 10 Mhz, the frequency and amplitude are spot on.

Phil Allison <pallison49@gmail.com>: May 04 04:43AM -0700 Jason Bowers wrote: =================== > dislodged during shipping. Reattached and a nice 2V PP 1 Khz square wave.   > Phil, what you said was confirmed. If I input the signal generator and > set for say 10 Mhz, the frequency and amplitude are spot on.   ** Thanks for the confirmation.   FYI: Analog scopes are one of my favorite things. I currently own 5 of them.   One I built from new parts when I was 17 - way back in 1970. Uses 5 tubes ( twin triode and triode pentode types ) plus is fully calibrated.   I also own a modern Rigol DSO but don't like it much ....       ..... Phil

Ralph Mowery <rmowery42@charter.net>: May 04 10:07AM -0400 In article <s6r5td$o4o$1@dont-email.me>, jbbowersnospam@aol.com says... > dislodged during shipping. Reattached and a nice 2V PP 1 Khz square wave.   > Phil, what you said was confirmed. If I input the signal generator and > set for say 10 Mhz, the frequency and amplitude are spot on.   Glad the scope checked out for you.   As far as the scope showing 2 or 3 waves at 30 MHz instead of one, that is probably normal. I checked out my Tecktronics 465B scope which is a 100 MHz scope and with the 10x button pushed in it shows several waves instead of just one at 100 MHz.   I think Phil mentioned it tht a scope is usually spected at a 3 db or some other figure down at the rating. Just like the 30 MHz scope has mostly full specs at 10 and not 30 MHz but is usuable to 30 and maybe some what more to look at waveforms. Then there is that square wave vers sine wave where you need a lot higher rated scope to show a true square wave than a sine wave.

Ralph Mowery <rmowery42@charter.net>: May 04 10:16AM -0400 In article <10e3bbf9-f1e4-4359-bd62-ee9a379f2848n@googlegroups.com>, pallison49@gmail.com says...   > I also own a modern Rigol DSO but don't like it much ....   Phil does your Rigol DSO work well in the X/Y mode ? I have a Hanteck that is similar to the Rigol DSO and for the most part the X/Y mode is not usuable. The one I have is a low end one that is a 200 MHz version.   I am like you, for many things I perfer the Techtronic 465B scope I have over the DSO, but for some things the DSO is better for me.   I did build a 2 inch scope in high school. I think it only had 3 tubes that handled the signals. One for the horizontal, one for the vertical, and one for the sweep generator. Couple of more were rectifiers. It probably topped out not much above the audio range.

"Miguel Giménez" <me@privacy.net>: May 04 02:53PM +0200 El 02/05/2021 a las 4:08, Jeroni Paul escribió:   > Hi Miguel, I hope you are all well.   > As others said this sounds like a problem with the speakers. The coil is glued to the plastic membrane and is now loose from one side. > I have had luck fixing some of these speakers. Depending on the speaker construction it may be easier to pull the magnet or separate the membrane from the frame. Either way once you get access to the coil you can glue it back, I use two component adhesive. Make sure you glue it exactly at the original position. Once dry glue the magnet/membrane back, the magnet may need centering, for that I apply an audio signal while the glue is not dry and center it for a loud and clear sound.   Thank you, Jeroni. Glad to hear from you again, after es.ciencia.electronica near defunction.   -- Saludos Miguel Giménez

Abandoned_Trolley <fred@fred-smith.uk>: May 03 08:32PM +0100 On 02/05/2021 20:30, Mike Coon wrote:   > Yes, it is one of the ways that "marine grade" wire is made more > expensive! The idea is that at sea you cannot guarantee that bare copper > wire will be protected from corrosion by the insulation.   some military grade wires are "made more expensive" by being silver plated - although they might look like they are tinned.   Also, the insulation is often of teflon instead of PVC   AT

Andrew Smallshaw <andrews@sdf.org>: May 03 08:32PM > some military grade wires are "made more expensive" by being silver > plated - although they might look like they are tinned.   > Also, the insulation is often of teflon instead of PVC   Sounds a lot like wire-wrap wire, a lot of them are ETFE or PTFE coated (it most definitely isn't all Kynar), silver plated. The plating is for corrosion resistance (particularly in wire wrapped joints) although there are some theoretical advantages at high frequencies I would generally consider the wire unsuitable at those speeds.   -- Andrew Smallshaw andrews@sdf.org

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