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Free 6 pin lemo cable and THS720 question


 

if anybody can use one,, I found another new 6 pin Lemo circular connector to tinned end cable from Tek, 20" long.
I believe Dennis said these were used to link to the TR50x style tracking generators, but not sure why one end is open.
In any case, free to anybody that can use it (not me), can ship in a cheap padded envelope anywhere.

TH720 Question: how can you check the battery condition? other than a low battery message on power up,
I have yet to find any way to check this, no menu brings it up that I can see. rats....

all the best,
walter


Mark Huffstutter
 

I think the 6 pin Lemo cable was used to connect the TR-502 Tracking Generator
To a 7L13, Walter. I remember reading a post by Dennis too.

Mark

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of walter shawlee
Sent: Saturday, August 29, 2020 10:32 AM
To: TekScopes@groups.io
Subject: [TekScopes] Free 6 pin lemo cable and THS720 question

if anybody can use one,, I found another new 6 pin Lemo circular connector to tinned end cable from Tek, 20" long.
I believe Dennis said these were used to link to the TR50x style tracking generators, but not sure why one end is open.
In any case, free to anybody that can use it (not me), can ship in a cheap padded envelope anywhere.

TH720 Question: how can you check the battery condition? other than a low battery message on power up,
I have yet to find any way to check this, no menu brings it up that I can see. rats....

all the best,
walter


 

On Sat, Aug 29, 2020 at 09:04 PM, Mark Huffstutter wrote:


I think the 6 pin Lemo cable was used to connect the TR-502 Tracking Generator
To a 7L13, Walter. I remember reading a post by Dennis too.
That cable has Lemo connectors on both sides.

Raymond


 

On Sat, Aug 29, 2020 at 07:32 PM, walter shawlee wrote:


TH720 Question: how can you check the battery condition? other than a low
battery message on power up,
I have yet to find any way to check this, no menu brings it up that I can see.
rats....
I assume you mean charge level, not wear-out or old age condition?
Charge level can be measured (to a certain degree as voltage per cell) by measuring voltage under load but AFAIK, the THS700-series don't support that as an indication other than by just by switching - or not powering on.
Since NiCd cells have a reasonably constant voltage until almost discharged, I usually took 1.05 - 1.1V as a minimum level. The indication possibilities by end-to-end measuring of a battery consisting of more than one cell in series are limited because of unknown differences in charge level. And that's just the start of it...

Raymond


Dave Casey
 

Walter's cable is probably for a word recognizer probe for the 2400 series
scopes, which uses the same 6 pin LEMO as the tracking generator cable, but
only on one end.

BTW, the tracking generator cable was used with both the 7L13 and 7L14
analyzers.


Dave Casey

On Sat, Aug 29, 2020 at 2:10 PM Raymond Domp Frank <@Raymond>
wrote:

On Sat, Aug 29, 2020 at 09:04 PM, Mark Huffstutter wrote:


I think the 6 pin Lemo cable was used to connect the TR-502 Tracking
Generator
To a 7L13, Walter. I remember reading a post by Dennis too.
That cable has Lemo connectors on both sides.

Raymond




BobH
 

As far as I know, there is no menu accessible way to see the battery condition on the THS720. I think that got added to the THS730, but that may be wishful recollection on my part.
One usability issue on the THS720 that is worth keeping in mind is that the two input channels do not share a ground. For low speed stuff with other scopes, I commonly just ground an unused input channel to the board under test and then wrap the ground lead of the probe that I am using arount the probe cable to keep it out ot the way. That does not work on the THS720! Each input channel must have it's own ground connection.
The THS720 is a really handy little scope! I like mine a lot. Thanks for the article on building the battery packs!
BobH