Date   

Re: Sony/Tek 380

Steven Bender
 

Hi Doug,

I also have a Sony/Tek 380 that shows no trace, I bought it as a cheap parts donor for my likewise no trace 335 and 336. Somewhere, someone recall mentioned his 335 having blown a Fuji 2SC3030 Darlington 900 Volt transistor in a flat TO-3P case. So, I bought a bunch of those on eBay recently its such a high voltage unit, the gain is only rated at 9! Testing one of the bunch, my little Chinese Tester said its gain was five (5). I guess, close enuf. Not sure if this part is a known failure mode in these no trace Sony/Tek 300 series sets, been to busy to attend to repairs on these units.

Hope that tidbit helps!


Steven L. Bender


Re: 2101 Pulse gen repair report

Michael Dunn
 
Edited

Thanks Tom, tho, a few notes:

On Fri, Apr 16, 2021 at 05:17 AM, Tom Lee wrote:
For the output amp, the NPNs are 2N3053 and the PNPs are 2N4036, replaceable
here by the venerable 2N2219A and 2N2905, respectively. Those parts are still
available cheaply.
Those parts are for baseline offset, not output amps per se. No AC requirements, so, yes, fairly easily subbed.

To "fix" the output amp, I just removed the offending transistor of the paralleled pair. The remaining part will be fine, as long as I don't push the output too hard.


Q182 is a 2N3563, replaceable by several devices in the 2N918/PN918/2N2857
family.
Which seem to be obsolete, or close enough to :-( At least here, a modern/available SMD could be kluged in if need be (even so, finding one with suitable DC spex may be tricky). I did find a suitable old part in my junk box (2N5179), though its DC specs may be marginal. I hope it lasts.


Be thankful that it's a 25MHz gen, rather than, say, a 100MHz one. You should
be able to find replacement transistors to keep it going pretty much forever.


Re: Maybe lots of tek scopes and plug-ins for sale

Miguel Work
 

Where are they located?

Do you have any contact information?

I¬īm interested is some stuff

-----Mensaje original-----
De: TekScopes@groups.io [mailto:TekScopes@groups.io] En nombre de Tony
Enviado el: viernes, 16 de abril de 2021 0:01
Para: TekScopes@groups.io
Asunto: Re: [TekScopes] Maybe lots of tek scopes and plug-ins for sale

Hi Dennis,



A couple bay area guys reached out directly, and they have this info now, but I'm also posting it here for everyone else to see.



http://encoreelectronics.com/tek/



I think a larger majority of it works, and I know the price is dependent on the working status. I was thinking people could make offers based on 80% of everything working, and then we could reduce it from there if we discover more failures that that. I'm not looking to take advantage of anyone, but I also want the same consideration. The more convenient someone can make this for me, the lower the price they'll pay. ūüėä



Thanks,

Tony

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of Dennis Tillman W7pF
Sent: Tuesday, April 13, 2021 5:49 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Maybe lots of tek scopes and plug-ins for sale



Hi Tony,

This is a chicken and egg situation. You want to know how much interest there might be but that would depend on what you have to sell and what you are asking for it. Likewise this might be the right place for it if there is enough interest in your inventory, its condition, and the proposed price. Any other place will want to know the same things so you have to make the first move and prepare an inventory list of equipment and its condition (working or not, etc).

Dennis Tillman W7pF



-----Original Message-----

From: <mailto:TekScopes@groups.io> TekScopes@groups.io [ <mailto:TekScopes@groups.io> mailto:TekScopes@groups.io] On Behalf Of Tony

Sent: Tuesday, April 13, 2021 5:03 PM

To: <mailto:TekScopes@groups.io> TekScopes@groups.io

Subject: Re: [TekScopes] Maybe lots of tek scopes and plug-ins for sale



Hello all,



I've been watching this group on and off for a long time, and have finally come around to the reality that I have too much stuff and will likely sell it all to free up space. There are a few mainframe chassis, and maybe 40 or 50 modules and a couple carts. I would rather NOT ship it anywhere, so I'm wonder if someone in Northern California would be interested in it as a group purchase? Of course I will have to inventory it all, but I wanted to see if anyone could point me to an appropriate place to sell this?



Thanks,

Tony

















--

Dennis Tillman W7pF

TekScopes Moderator


Ghost spot on a 2445 sreen

f5dog
 

Hi.
This topic again about a strange thing on the screen of a 2445.
A ghost, not focused spot flashes randomly at a stable location on the screen, whatever the brightness setup, vertical scaling, tme base, triggering, etc...
When the scope is turned off, this spot remains visible during about one minute, before disapearing. A possible source could be a default regarding not enough screening from high voltage area, or a leakage problem, considering discharging capacitor time as an information to investigate the root cause of this ghost spot near the middle of the screen.
Waiting for any help or advice, if any idea or known problem.
Thanks and regards.
John.


Re: 2101 Pulse gen repair report

Tom Lee
 

For the output amp, the NPNs are 2N3053 and the PNPs are 2N4036, replaceable here by the venerable 2N2219A and 2N2905, respectively. Those parts are still available cheaply.

Q182 is a 2N3563, replaceable by several devices in the 2N918/PN918/2N2857 family.

Be thankful that it's a 25MHz gen, rather than, say, a 100MHz one. You should be able to find replacement transistors to keep it going pretty much forever.

Cheers,
Tom


Sent from an iThing, so please forgive the typos and brevity

On Feb 3, 2021, at 11:16, "Michael Dunn" <md@cantares.on.ca> wrote:

Well, I might be a bit rusty, but it seems I can still repair things :-) In this case, the versatile 2101 pulse generator from 1970.

I had no idea of its condition, so first off, I wiggled all the socketed transistors, then turned it on, saw *some* sort of output, and checked all the supplies (all perfectly fine after 50 years :-) The two shaft couplings are partly broken…I’ll probably just glue them or something :-(

While playing and familiarizing myself with the gear, it suddenly died. Ugh. I thought this would be easy. The core oscillator circuit was still running though, and I finally tracked the culprit to Q182, part of the pulse forming circuitry. The transistor measures largely open now. Weird…suddenly going from working to very dead like that. I stole the corresponding transistor from the delayed pulse generator. Hopefully there is a suitable sub in my junk box.

Next, a more subtle problem. The negative pulse output had a few volts of negative baseline offset. It took me a while to grok the complex output amp circuitry (it‚Äôs still somewhat mysterious to me), but after a couple of false trails, I returned to an early hunch: the final, paralleled, output transistors. Sure enough, one of them (Q352) is bad, showing under 1 kő© from B to C.

Yay…a mostly working unit.

Finding a TO-39 part for the output transistor might be tricky. I do have quite a few in the junk box, but whether any will have good enough AC specs…??? It does kinda hafta be that package, as the heatsink is made to fit it.

As for Q182, it‚Äôs an RF transistor‚ÄĒI may have a suitable sub lying around‚Ķ

So…transistors. Available selection these days seems pretty sad. Am I right, or not? Especially in leaded (no surprise there). The four types of SS xstrs in the 2101 fall into an NPN/PNP-RF/Switching matrix. I sure hope a PNP switch never fails, cuz I couldn’t find a single example at Digikey, regardless of package…

I should know this, but do we have a Tek parts cross reference somewhere in the files? Quite a few parts in the 2101 have no description beyond ‚ÄúTek Spec‚Ä̂Ķ












Please wrap this up.: RE: [TekScopes] OT: microscope source?

 

40 messages on an off-topic subject is excessive.
I think by now Brad Thompson has enough information to make a decision about Amacope and many other microscopes that may be an aid to his failing vision.
If Brad has any additional questions this would be a good time to ask them.
If anyone wishes to continue the conversation please take it off-line.
Dennis Tillman W7pF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Tom Gardner
Sent: Thursday, April 15, 2021 3:49 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] OT: microscope source?

On 15/04/21 22:06, Roy Thistle wrote:
On Thu, Apr 15, 2021 at 01:36 AM, Tom Gardner wrote:

I suggest it might be worth some quick and cheap experiments to help
you decide on your equipment.
All these headband thingys seem cheaper on Ebay (but maybe not if you
have Amazon prime.) I find a dizzying plethora of them.. on Amazon, Ebay... and tellingly... less on Bangood!
And just and only in my personal opinion... they are all sub-useful. I say that because... again in my opinion... when Chinese manufacturers find a design that "works" they stick with it... and everyone just copies it. Obviously, they haven't found one they like, at the price point they like. The whole mess of these things is likely junk.
As I noted, they are widely available.

As for being "junk", the type I referred to

* work extremely well for my eyesight and my work
* has been replaced once after 6 years - but at that price it is perfectly
possible to regard it as a consumable

so I don't recognise your meaning of junk.

But as I also noted, YMMV.








--
Dennis Tillman W7pF
TekScopes Moderator


Re: Sony/Tek 380

 

Check the blanking.

On 4/15/2021 9:25 PM, Doug wrote:
I picked up a little Sony/Tektronix 380 Video Waveform/Vectorscope recently. It powered up but no trace,
just a faint glow on the screen. It looked to me that the X10 HV multiplier was bad so I dug out the epoxy
and made a new one. Now the glow is bright but still no trace and the brightness is not affected at all by
the intensity control or the grid bias trimmer, which leads me to believe the CRT is bad.

I have voltage on the focus grid and I tried disconnecting the H and V plates - no change

I removed the CRT to look at the insides. Nothing looks broken or out of place as far as I can tell.
The grid bias trimmer varies the heater to grid voltage from 70V to 130V with, as I said, no intensity change.
Heater is at -1950V.

Looks to me like the CRT is bad. Am I missing anything? Any suggestions?

I've posted some photos under "380".



--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Sony/Tek 380

Doug
 

I picked up a little Sony/Tektronix 380 Video Waveform/Vectorscope recently. It powered up but no trace,
just a faint glow on the screen. It looked to me that the X10 HV multiplier was bad so I dug out the epoxy
and made a new one. Now the glow is bright but still no trace and the brightness is not affected at all by
the intensity control or the grid bias trimmer, which leads me to believe the CRT is bad.

I have voltage on the focus grid and I tried disconnecting the H and V plates - no change

I removed the CRT to look at the insides. Nothing looks broken or out of place as far as I can tell.
The grid bias trimmer varies the heater to grid voltage from 70V to 130V with, as I said, no intensity change.
Heater is at -1950V.

Looks to me like the CRT is bad. Am I missing anything? Any suggestions?

I've posted some photos under "380".


Re: Snubber vs safety cap in 7854.

Martin Hodge
 

On Thu, Apr 15, 2021 at 06:04 PM, Roy Thistle wrote:


Hi Martin:
Well there is already a line filter before the switch ... but, I don't know if
the line filter has line to line X... and line to chassis Y... you could
check.
The only reason for R5, C5, C6 ... that I can see is to protect the bridge
rectifier.
Are you saying that Tektronix moded those out in an updated version of the
schematic?

--
Roy Thistle
Well hey, it's right there in the manual:

"LINE INPUT
Power is applied through line filter FL10, line fuse F10,
and POWER switch S10. The line filter is designed to
keep powerline interference from entering the
instrument and to keep the approximate 25-kilohertz
Inverter signal from entering the power line. Components
R5, C5 and C6 suppress reverse-recovery transients of
CR15"

I'll turn 50 this year. You'd think by now I'd have learned to read the manual.
So, yeah, Tek replaced those three components with one monolithic package made by Rifa.


Re: OT: microscope source?

Tom Gardner
 

On 15/04/21 22:06, Roy Thistle wrote:
On Thu, Apr 15, 2021 at 01:36 AM, Tom Gardner wrote:

I suggest it might be worth some quick and cheap experiments to help you
decide on your equipment.
All these headband thingys seem cheaper on Ebay (but maybe not if you have Amazon prime.)
I find a dizzying plethora of them.. on Amazon, Ebay... and tellingly... less on Bangood!
And just and only in my personal opinion... they are all sub-useful. I say that because... again in my opinion... when Chinese manufacturers find a design that "works" they stick with it... and everyone just copies it. Obviously, they haven't found one they like, at the price point they like. The whole mess of these things is likely junk.
As I noted, they are widely available.

As for being "junk", the type I referred to

* work extremely well for my eyesight and my work
* has been replaced once after 6 years - but at that price it is perfectly
possible to regard it as a consumable

so I don't recognise your meaning of junk.

But as I also noted, YMMV.


Re: Snubber vs safety cap in 7854.

Roy Thistle
 

Hi Martin:
Well there is already a line filter before the switch ... but, I don't know if the line filter has line to line X... and line to chassis Y... you could check.
The only reason for R5, C5, C6 ... that I can see is to protect the bridge rectifier.
Are you saying that Tektronix moded those out in an updated version of the schematic?

--
Roy Thistle


Re: Maybe lots of tek scopes and plug-ins for sale

Tony <tony@...>
 

Hi Dennis,



A couple bay area guys reached out directly, and they have this info now, but I'm also posting it here for everyone else to see.



http://encoreelectronics.com/tek/



I think a larger majority of it works, and I know the price is dependent on the working status. I was thinking people could make offers based on 80% of everything working, and then we could reduce it from there if we discover more failures that that. I'm not looking to take advantage of anyone, but I also want the same consideration. The more convenient someone can make this for me, the lower the price they'll pay. ūüėä



Thanks,

Tony

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of Dennis Tillman W7pF
Sent: Tuesday, April 13, 2021 5:49 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Maybe lots of tek scopes and plug-ins for sale



Hi Tony,

This is a chicken and egg situation. You want to know how much interest there might be but that would depend on what you have to sell and what you are asking for it. Likewise this might be the right place for it if there is enough interest in your inventory, its condition, and the proposed price. Any other place will want to know the same things so you have to make the first move and prepare an inventory list of equipment and its condition (working or not, etc).

Dennis Tillman W7pF



-----Original Message-----

From: <mailto:TekScopes@groups.io> TekScopes@groups.io [ <mailto:TekScopes@groups.io> mailto:TekScopes@groups.io] On Behalf Of Tony

Sent: Tuesday, April 13, 2021 5:03 PM

To: <mailto:TekScopes@groups.io> TekScopes@groups.io

Subject: Re: [TekScopes] Maybe lots of tek scopes and plug-ins for sale



Hello all,



I've been watching this group on and off for a long time, and have finally come around to the reality that I have too much stuff and will likely sell it all to free up space. There are a few mainframe chassis, and maybe 40 or 50 modules and a couple carts. I would rather NOT ship it anywhere, so I'm wonder if someone in Northern California would be interested in it as a group purchase? Of course I will have to inventory it all, but I wanted to see if anyone could point me to an appropriate place to sell this?



Thanks,

Tony

















--

Dennis Tillman W7pF

TekScopes Moderator


Re: 465 Digital Storage scope

Roy Thistle
 

On Tue, Apr 13, 2021 at 02:44 PM, zenith5106 wrote:


No, it was a Custom Mod that could be ordered for an extra $1300 in 1979
If you got it back then, you were paying towards the development of the 468... since the top interface on the one on Ebay is more primitive: 2 pots for horizontal cursors, and missing the storage options of the 468.
I was not impressed by the 468, even relative to its TTL 8 bit era.
Impress me.

--
Roy Thistle


Re: 465 Digital Storage scope

Roy Thistle
 

On Tue, Apr 13, 2021 at 01:02 PM, zenith5106 wrote:


A couple of weeks back there were discussions on a 2215A with digital storage
which most people,
including me, initially thought was a fake until we saw the pictures.
I missed that discussion about the 2215A with the digital storage... but either there is one here... somewhere... or I saw one for sale at a local auction. Well, I never saw Bigfoot; but, I did see a 2215A with digital storage... though I thought it was a bodge.

--
Roy Thistle


Re: OT: microscope source?

Harvey White
 

The Spencer I have is AO optical, and the price was reasonable enough.  I have a fiber optics ring light where I run the projector lamp at the minimum voltage, and it has lasted years.  I do throw in some extra light as needed.

I'm using the microscope for assembly, and then inspection afterwards.  It seems to work for me well enough, so I don't see changing it.  At the time I was looking for this Leica, Zeiss, and the like were three hundred dollars and up, mostly up.  It was a bit more than I wanted to spend.

Harvey

On 4/15/2021 3:17 PM, magnustoelle via groups.io wrote:
Good day,
I appreciate all the good advice based on 1st hand experience.
Harvey, if you are looking into microscopes for¬†inspection, not active work when microscoping, then I‚Äėd recommend some quality¬†Stereo Microscopes from brands such as Leica, Olympus or Zeiss.Th Their¬†adjustable magnification power is a feature I surely do not want to miss. ‚ÄöZooming‚Äô¬†in and out the¬†area of interest is what I do most before and after equipment¬†repair work and board assembly.
After weeks of¬†consideration I have bought a used Zeiss type Stemi¬†DV4 in good condition last year; with a¬†magnification of¬†8x to 32x. Its optics are stunning.The 2nd aspect I want to mention is good lighting. You cannot expect good visuals under poor lighting conditions. Good light systems can be expensive!¬†¬†I have converted two¬†inexpensive work lights with goose necks¬†into adjustable and¬†dimmable lights for the above microscope and¬†in¬†combination with the Stereo Microscope they¬†produce¬†excellent results; at a¬†hobby budget friendly price level¬†(total 400‚ā¨).There are many threads on this topic on the eevblog forum.
Cheers,
Magnus


Harvey,

The first microscope you mention is a stereo microscope, but the second microscope, I believe, is a reflected light high power microscope for wafer inspection is not a stereo microscope.
It is binocular, but not stereo. There is one light path that is split into two eyepieces, so it cannot be stereo.

--Victor

On Thu, Apr 15, 2021 at 12:07 PM, Harvey White wrote:

If you're going to get a stereo microscope, bear in mind that there are
two industry uses at least.  One is parts inspection, assembly and
such.  These have a suitable working distance, say 4 to 6 inches based
on what I have.

The other type is a wafer inspection scope.  It has a very short working
distance and is not suitable (IMHO) for assembly work. You can often
tell the difference by looking at the stage.  The wafer scope should
have positioning adjustments on the stage.

I have an american optical /spencer on a boom.  Useful for assembly, but
not useful for peering inside a plugin.

Harvey











Re: OT: microscope source?

Roy Thistle
 

On Thu, Apr 15, 2021 at 09:20 AM, Daniel Koller wrote:


And I am STUNNED at how good these eyepieces are.
There are definitely bad cheap optics... and not so surprisingly good... even very good cheap optics. It's a mature technology ... perhaps there are newer glasses, and newer coatings (these things may not be better)... but making the very good lenses at scale is very cheap... especially in Asia, and especially for such a huge marked there.
Long gone are the German guilds of lens makers... at least on industrial scale.

--
Roy Thistle


Re: OT: microscope source?

Harvey White
 

Ok, and thanks.

I've seen both at hamfests, and they look more or less identical.  I was mentioning this because I didn't want people to mistake the two and buy the wrong one.

Thanks, this ought to make it more obvious.

Harvey

On 4/15/2021 2:54 PM, victor.silva via groups.io wrote:
Harvey,

The first microscope you mention is a stereo microscope, but the second microscope, I believe, is a reflected light high power microscope for wafer inspection is not a stereo microscope.
It is binocular, but not stereo. There is one light path that is split into two eyepieces, so it cannot be stereo.

--Victor

On Thu, Apr 15, 2021 at 12:07 PM, Harvey White wrote:

If you're going to get a stereo microscope, bear in mind that there are
two industry uses at least.  One is parts inspection, assembly and
such.  These have a suitable working distance, say 4 to 6 inches based
on what I have.

The other type is a wafer inspection scope.  It has a very short working
distance and is not suitable (IMHO) for assembly work. You can often
tell the difference by looking at the stage.  The wafer scope should
have positioning adjustments on the stage.

I have an american optical /spencer on a boom.  Useful for assembly, but
not useful for peering inside a plugin.

Harvey



Re: OT: microscope source?

Roy Thistle
 

On Wed, Apr 14, 2021 at 07:55 PM, Ken Eckert wrote:


a boom stand is a must from my viewpoint.
They can be awkward... and that's some of the reason why industrial manufactures dropped them as soon as they could.
They give adequate movement, and positioning; but take up a lot of swing space, and the base has to be mounted solidly... or is very heavy (maybe 40 pounds... or more.)
--
Roy Thistle


Re: OT: microscope source?

Roy Thistle
 

On Thu, Apr 15, 2021 at 01:36 AM, Tom Gardner wrote:


I suggest it might be worth some quick and cheap experiments to help you
decide on your equipment.
All these headband thingys seem cheaper on Ebay (but maybe not if you have Amazon prime.)
I find a dizzying plethora of them.. on Amazon, Ebay... and tellingly... less on Bangood!
And just and only in my personal opinion... they are all sub-useful. I say that because... again in my opinion... when Chinese manufacturers find a design that "works" they stick with it... and everyone just copies it. Obviously, they haven't found one they like, at the price point they like. The whole mess of these things is likely junk.

--
Roy Thistle


Re: OT: microscope source?

stevenhorii
 

Your methods have some similarity to arthroscopic surgery and
interventional radiology. It has caused us (meaning surgeons and
radiologists) to raise some questions - in both situations, you are often
not directly viewing your hands or your instruments. You are viewing them
on a monitor. We know the methods are necessary - arthroscopic, endoscopic,
and laparoscopic procedures are examples and that they are successful. The
interesting question was whether the ‚Äúgaming generation‚ÄĚ that is used to
looking at results of what their hands are doing on a monitor rather than
watching or seeing their hands directly, would turn out to be better at
these ‚Äúindirect observation‚ÄĚ procedures. I‚Äôll have to track down the
reference, but there was a study that showed that those who had extensive
computer gaming experience adapted more quickly to indirect observation
procedures.

I have done some work on electronic equipment when I could not directly see
what my ‚Äútarget‚ÄĚ was and had to rely on a view through a video borescope
(the non-medical ones have gotten very reasonably priced). I had to loosen
a set screw that I could not see directly (this sounds like some of the
problems reaching certain parts in Tek scopes) so I guided the tip of the
Allen key using my view with the borescope display which was on a small
monitor. Oh, and I also tend to use surgical instruments for work on
equipment. Hemostats and forceps are quite useful! A pair of long forceps
is great for retrieving a screw or nut dropped inside a chassis. Anyone who
wants to know more about how I use these things can contact me privately as
this is way off topic.

Steve Horii

On Thu, Apr 15, 2021 at 15:38 Vince Vielhaber <vev@michvhf.com> wrote:

I use one like this:

https://www.ebay.com/itm/143647752810

I suspend it above the bench and have it showing on the 23" monitor in
front of me. I did some component level on a Yaesu 857D where some of
the parts were so tiny my SMD pickup tool ate em. Using an exacto knive
I launched a few across the room never to be found again. Good thing I
bought the parts in quantities of 25+, I lost many!!

Vince.




On 04/15/2021 04:52 AM, cheater cheater wrote:
There's only one microscope you should be buying and it's the exact
one Louis Rossmann sells, bought directly from Louis Rossmann. He has
a special version that isn't sold anywhere else. He explains it in his
videos at some point, hell if I can find them.

If someone can point to a better scope, at this sort of price, I'm all
ears.

Here's a trick though. My vision isn't that great either. But I can
solder 01005 without a problem. How?

I have some large windows looking out into the northern sky
(important), and I solder on the window sill. The light is just so
much better than any artificial source you can get, and it improves
your vision dramatically. Do yourself a favor and try this trick.

Cheers

On Thu, Apr 15, 2021 at 10:36 AM Tom Gardner <tggzzz@gmail.com> wrote:

Welcome to that club :(

The choice is going to be very personal; what suits my eyes and working
habits
may not be suitable for you.

Since you /will/ end up doing some experimentation, I suggest it might
be worth
some quick and cheap experiments to help you decide on your equipment.
In that
vein, I suggest you try these
https://www.amazon.co.uk/COVVY-Magnifier-Magnifying-Detachable-Electronic/dp/B07P957H9Z


* cheap enough to be regarded as disposable
* very widely available under many brand names from many sources
* work with your spectacles
* no problem getting a soldering iron between the lenses and the UUT
* flux residue not deposited on lenses
* work at any angle, including peering sideways into equipment cases
* multiple magnifications
* useless LED light



On 15/04/21 02:36, Brad Thompson wrote:
Hello--

Given shrinking component markings and deteriorating vision, I'm
interested in purchasing a stereo microscope with long working
distance.
I stumbled across a company (Amscope) that offers a range of scopes
that
look promising.

Has anyone in the group purchased from that company? Please reply
privately.

On a broader level, what's the group's experience and recommendations
for peering, say, into a plug-in's innards?

Thanks in advance, and 73--







--
K8ZW http://www.metalworkingfun.com http://www.hamradio.fun





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