Model HP 3400a with an enlarged case has an int/ext load switch...

[amdx]

 I\'m looking at an HP 3400A with an enlarged case to the side,
containing an internal/external load switch
 and another switch to pick 600Ω, 150Ω, 75Ω and VM. What would VM stand
for?

                                         Thanks, Mikek

 

[amdx]

On 9/2/2022 2:39 PM, amdx wrote:

 I\'m looking at an HP 3400A with an enlarged case to the side,
containing an internal/external load switch
 and another switch to pick 600Ω, 150Ω, 75Ω and VM. What would VM
stand for?

                                         Thanks, Mikek

  Is it as simple as Voltmeter?
                      Mikek

 

[piglet]

On 02/09/2022 20:53, amdx wrote:

On 9/2/2022 2:39 PM, amdx wrote:
 I\'m looking at an HP 3400A with an enlarged case to the side,
containing an internal/external load switch
 and another switch to pick 600Ω, 150Ω, 75Ω and VM. What would VM
stand for?

                                         Thanks, Mikek
  Is it as simple as Voltmeter?
                      Mikek

Can you check with an ohmmeter?

piglet

 

[amdx]

On 9/3/2022 1:30 AM, piglet wrote:

On 02/09/2022 20:53, amdx wrote:
On 9/2/2022 2:39 PM, amdx wrote:
 I\'m looking at an HP 3400A with an enlarged case to the side,
containing an internal/external load switch
 and another switch to pick 600Ω, 150Ω, 75Ω and VM. What would VM
stand for?

                                         Thanks, Mikek
   Is it as simple as Voltmeter?
                       Mikek

Can you check with an ohmmeter?

piglet

I don\'t have it, I\'m thinking about buying it.
 It make sense to me that VM switch position has no termination, that
is how the basic 3400A is, you need to put your own,
termination on the unit to terminate the input cable.

  I\'m leaning towards VM = voltmeter, normally the 3400A has a
10MΩ/15pf to 40pf input impedance,
depending on range, so, theoretically it can be used as a high impedance
voltmeter with
much caution paid to input connection.

   Mikek

 

[amdx]

On 9/3/2022 7:53 AM, amdx wrote:

On 9/3/2022 1:30 AM, piglet wrote:
On 02/09/2022 20:53, amdx wrote:
On 9/2/2022 2:39 PM, amdx wrote:
 I\'m looking at an HP 3400A with an enlarged case to the side,
containing an internal/external load switch
 and another switch to pick 600Ω, 150Ω, 75Ω and VM. What would VM
stand for?

                                         Thanks, Mikek
   Is it as simple as Voltmeter?
                       Mikek

Can you check with an ohmmeter?

piglet

I don\'t have it, I\'m thinking about buying it.
 It make sense to me that VM switch position has no termination, that
is how the basic 3400A is, you need to put your own,
termination on the unit to terminate the input cable.

  I\'m leaning towards VM = voltmeter, normally the 3400A has a
10MΩ/15pf to 40pf input impedance,
depending on range, so, theoretically it can be used as a high
impedance voltmeter with
much caution paid to input connection.

   Mikek

I inclined to bid on it at the last second, I\'m now sorry I missed it.
A $70 bid would have got it, I\'ll probably never get one that cheap.
Although shipping was another $34. I have one already on the way, need
to see if it\'s fixable before a put another on the shelf.
                      Mikek