This looks pretty good. I don’t know anything about the seller though.

https://www.ebay.com/itm/Tektronix-1S1-Sampling-Unit-Oscilloscope-Plug-In-Module-Free-Shipping/393086861150?hash=item5b85cd7f5e:g:NNAAAOSw4FRf92XF

Almost too good to be true.

Wow that didn’t last long. If someone here got it, congrats and you are welcome!

Wow, you don't see many 1S1s these days, and not at that price! At best the unit still works, otherwise I predict in a few weeks we'll get a new member with many questions about getting a 1S1 to work.

from Tim P (UK)

Yes, I expect the lucky owner may well be asking about the 1S1 and it's
foibles !
I have four - one works, but needs the Loop Gain tweaking every time I use
it, one triggers but won't sweep, (nothing at the Horiz Out jack), one
free-runs but won't trigger, and one won't sample, although I see strobe
pulses. The Diode Dance of Death ?

Tim


On Tue, 12 Jan 2021 at 04:47, snapdiode via groups.io <snapdiode=
yahoo.com@groups.io> wrote:

Wow, you don't see many 1S1s these days, and not at that price! At best
the unit still works, otherwise I predict in a few weeks we'll get a new
member with many questions about getting a 1S1 to work.

It must have been. The auction is now "ended" but not shown as sold.

I don't think eBay marks auctions as "sold" or "complete" until the item is paid for. Also, for non-BIN auctions, "ended" can mean the listing duration has expired without any bids (or bids meeting the reserve price).

Loop gain is sensitively dependent on the amplitude of the snapoff pulse and the cathode temp of the tube. My 1S1 is fitted with a heater regulator board that was not regulating due to a short; it is more stable now that I fixed it.

I added my repair notes at https://w140.com/tekwiki/wiki/1S1? .


HTH,

Dave Wise

________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of Tim Phillips via groups.io <timexucl=gmail.com@groups.io>
Sent: Tuesday, January 12, 2021 1:15 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] 1s1 on ebay

from Tim P (UK)

Yes, I expect the lucky owner may well be asking about the 1S1 and it's
foibles !
I have four - one works, but needs the Loop Gain tweaking every time I use
it, one triggers but won't sweep, (nothing at the Horiz Out jack), one
free-runs but won't trigger, and one won't sample, although I see strobe
pulses. The Diode Dance of Death ?

Tim

If you click on See Original Listing you will find this:

Sold for: US $49.95

Vince.

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

It didn't show sold when I looked at it earlier. SC must be right about
them not showing sold until the item is paid for.

I also own four! We're twins! I also have one that barely works, the rest are just too much trouble to get working. One of them needs a deep cleaning too.

I have found myself stumped by the -139/-138V system.

Of course, the two missing 8416s, no doubt sold off to AudioPhool Land,
Would take some of the Fun out of it....

Mark

Woops, well that explains the price. I hope the buyer noticed.

If you go by eBay prices, buying two 8416s will bring that "bargain" 1S1 in line with the 200$ range I see for 1S1s these days,

?I have on my "to do someday" list, adjusting the heater current to acommodate 12AT7 and see if it's acceptable.


Dave Wise

________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of snapdiode via groups.io <snapdiode=yahoo.com@groups.io>
Sent: Tuesday, January 12, 2021 10:54 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] 1s1 on ebay

If you go by eBay prices, buying two 8416s will bring that "bargain" 1S1 in line with the 200$ range I see for 1S1s these days,

Or figure out a solid-state replacement...