This caught my eye on Bay today:
https://www.ebay.com/itm/143483702797
"Tektronix Oscilloscope MOD 709V W/ 5A19N Amp, 5A19N Diff. Amp, 5B10N Time/Base"

All I could get out of Google was one more add for another instance of the same thing:
https://www.nriparts.com/products/tektronix-5110-mod-709v/325390
"Tektronix 5110 MOD 709V Oscilloscope"

What both of those headlines miss is the "Bently Nevada" branding. A little more poking around suggests that was a legit thing for an application that continues today, but that particular scope has disappeared except for the two listings.

I dumped what I found on TekWiki: https://w140.com/tekwiki/wiki/Bently_Nevada_5110_Mod_709V

Anyone here know anything more?

On Sun, Feb 7, 2021 at 08:47 AM, Paul McClay wrote:

Anyone here know anything more?

From the mod 709V manual:

//
DESCRIPTION
This manual describes MOD 709V as it applies to the
TEKTRONIX 5110 Single Beam Oscilloscope. MOD 709V
adds a new circuit board for X-Y operation using Right
Vertical versus Left Vertical. Using a TEKTRONIX 5B10N
MOD 709V Time Base plug-in unit, the SECONDS/DIV or
VOLTS/DIV switch is turned to the L versus R position
actuating a switching relay mounted in the mainframe. This
bypasses the normal sweep function of the 5B10N, allowing
for a Left Vertical versus Right Vertical X-Y display. The
display unit portion of the 5110 is supplied with an
illuminated graticule with a special implosion shield, and an
AC coupled EXT INTENSITY INPUT via a yellow binding post
at the front panel.
Bandwidth: Maximum horizontal deflection bandwidth
(using a 5A15N or 5A18N amplifier) is reduced by
approximately 300 kHz by the added wiring. Bandwidth (-3 dB)
for X-axis deflection from either the center or right compartment
is 1.7 MHz minimum. The Y-axis specification is unchanged.

CALIBRATION:
Check the interconnecting wiring to the added X-Y circuit board,
then calibrate MOD 709V according to the procedure in the 5110
Instruction Manual.
//

/Håkan

Thanks Håkan!

From a look at your panorama of Tek gear, and fische reader, I should not be surprised that you have the manual!

A few more questions:

May I add that excerpt to TekWiki?

Do you have any digital copy of the manual? Or a part number for the manual?

Does Mod 709V include the other colored binding posts on the plugins?

===

I wonder if the story of how this mod came to be and who bought it includes anyone other than Bently Nevada.

On Sun, Feb 7, 2021 at 09:00 PM, Paul McClay wrote:

May I add that excerpt to TekWiki?

Off course

Do you have any digital copy of the manual? Or a part number for the manual?

No, only on micro fiche and I don't have a working M/F scanner.
These are not manuals but Manual Inserts which was supposed to be added to the original manual.
As such they did not have a 070- number. Some might have document number and on the scope
insert there was a handwritten number as 061-1473-00. Nothing on the plugins.

Does Mod 709V include the other colored binding posts on the plugins?

The mod info on the plugins:
//
5A19N MOD 709V
This manual insert describes the features of MOD 709V as installed in the 5A19N
Differential Amplifier. The Signal Input connector has been changed to a blue
binding post for the Minus Input. The Variable VOLTS/DIV control labeled CAL
has been removed. A +15 Volts offset, regardless of the VOLTS/DIV control
setting has been added

5B10N MOD 709V
This manual insert describes the features of MOD 709V as installed in the 5B10N
Time Base Amplifier. It removes the VAR control, changes the BNC EXT INPUT
connector to a green binding post and provides a switching mode for
Left Vertical vs Right Vertical, The last ccw position of the SECONDS/DIV or
VOLTS/DIV (EXT) switch is now labeled L vs H.
//

/Håkan

Thanks again for the add'l info - and for taking the time to transcribe it. I've added it to TekWiki.

Interesting that the timebase mode switch apparently differs between the doc & photographed units.

A couple more questions:

Is "L vs H" correct for the 5B10N switch mod? That seems odd when the function is, I assume, Left vertical amp vs _not_ Horizontal sweep.

Are "Description", "Bandwidth" & "Calibration" same-level headings? Or Description & Calibration with Bandwidth under Description? Or otherwise?

Thanks again for help with the real reference material.

On Mon, Feb 8, 2021 at 08:17 AM, Paul McClay wrote:

Is "L vs H" correct for the 5B10N switch mod? That seems odd when the function I assume, Left vertical amp vs _not_ Horizontal sweep.

Yes off course it should be L vs R

Are "Description", "Bandwidth" & "Calibration" same-level headings? Or Description & Calibration with Bandwidth under Description? Or otherwise?

I'm not sure understand the question correctly .... but here is what is said about Calibration:

//
5A19 MOD 709V CALIBRATION

Calibrate the same as standard with the following additions regarding offset.

Check OFFSET for ±15 volts in all Volts/Div positions.

1. Ground amplifier inputs and set display in center screen with
OFFSET in OFF position, and Volts/Div in .5 Volt/Div position.

2.Turn OFFSET to ON position and position trace 1 cm above center
screen. Plus .5 volts OFFSET.

3. Change Volts/Div to .2 position. Trace should now be 2-1/2 cm
above center screen. If trace shifts toward center screen instead,
offset strap on board is in wrong position. Strap should be in
position #2.

5B10 MOD 709V CALIBRATION

Calibrate this instrument the same as standard except as follows:

1. Variable TIME/DIV is deleted - no checks required.

2. Fully ccw position of TIME/DIV switch used to be EXT INPUT .5 VOLTS
PER DIV. This feature is deleted and is now marked L vs R (left vertical versus
right vertical). In this position check to see that -30 volts is present at
contact A-12 of interface connector. Voltage should not appear at A-12 in any
other position of timing switch.
//

/Håkan

Thanks again Håkan for transcribing the add'l info. It fills in some understanding.
I've added it to the wiki.

The "headings" question was more about how to format around the excerpts. I think I've got it close enough with a note to distinguish the adapted headings from directly transcribed text.