FS: Parts from an 8515A 26.5 GHz S-parameter test set (used on 8510 VNAs)

Dr. David Kirkby (Kirkby Microwave Ltd)

Over the next few weeks I will be stripping down an 8515A S-parameter test set. I will not be selling the bridges, but anything else might be up for grabs.

If you have any damaged or missing parts, send me a photo, part number and offer. Send it off-list.

Dave

Re: HP 83592B hangs 8350B sweeper

#71856

开云体育

Hi Peter, I have done this calibration several ?time , I think ?the A vs B is the X-Y display on the scope , I was using the HP 1740A oscilloscope to do this. The intensity must set to the high position because it is difficult to see the crest of the ramp to 0V.

Regards

ON1EV

Belgium

De?: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
贰苍惫辞测é?: dimanche 18 octobre 2015 01:48
??: hp_agilent_equipment@...
Objet?: RE: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

Has anyone done a calibration on one of these plug-ins?

Step 20 in adjustments: What does A vs B mode on an oscilloscope mean? I think HP means trigger on B and look at A ??(A + B or A – B will not work. The waveforms are completely different time/div and shapes)

A6-TP8 does not have positive sweeps as shown. They go negative from 0 to -10v.

Step 22: A6R37 will not affect TP8 an far as I can see.

Am I missing something?

?

Show quoted text

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: October-17-15 5:54 PM
To: hp_agilent_equipment@...
Subject: RE: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

GREAT PROGRESS!

Thanks Steve, you are quite correct. My A7 board is marked 83595 and works in this 83592 plug-in.

However I suspected that the A6 board that was causing all the trouble was actually from an 83595 not an 83592. I removed the 4L and 4H pots, installed the R63 pot, moved the Band jumper, ?and concentrated on the Sweep Control and Bandswitch circuits.

The A3 SW1 forces the signals to go through the variable gain amplifier for troubleshooting. Using this setting I could sweep band 0 but was finding that the TP7 signal was going positive by 2.4 volts. It should start at 0v and go negative to -10v max. There was an offset in the variable gain amplifier! I had also noticed that the gain seemed high. The schematics showed the gain resistors to be the same as the ones on the bad A6 board but they were different from the ones on the good A6 board. The parts list agreed with the resistors on the good A6 board so I assumed them to be correct. This was not the first error on the schematics I had found.

Troubleshooting: Set sweep from 1 MHz to 1.1 MHz so TP5 is essentially at 0v. Check TP1 (BandSw DAC O/P) is 1.195v on good A6 and 1.194 on bad A6. So far so good. Check U5-6 is -10.05v on good A6 but is? -12.73v on bad board. TP7 is 0v on the good A6 but is +2.4v on the bad board. Conclusion: the gain is too high and is tripping U14 in the Bandswitch Comparator.

Change all 4 gain resistors:

R29???????? B0?????????? was 109.73k??????? change to 82.541k (TP7 is now 0v with the above test)

R27???????? B1?????????? was 57.014k??????? change to 42.884k

R25???????? B2?????????? was 40.423k??????? change to 30.423k

R23???????? B3????????? was 40.423k??????? change to 30.423k

Now the plug-in sweeps from 0.01 to 20 GHz and the INSTR PRESET no longer hangs the 8350B.

Conclusion: The A6 board was from an HP 83595. I can now proceed with the calibration bu expect some problems because the resistors I used were 1%, not 0.1%, and are not the exact values. I may not have enough range of adjustment. I may also run into problems in the SRD and PIN diode bias circuits because of component values.

Some of the analog switches are normally closed (PMI SW06) but are shown open on the schematic. U2A pins 1 & 2 are switched, U2A-2 goes to U13-11.

Peter.

?

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: October-16-15 12:10 PM
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

Peter,

?

I have an 83594A and an 83595A wth boards that have mismatched part numbers so it may not have been anything nefarious but if so its contagious! There are a couple of boards that don't match any of the manuals I've been able to find, and there are switches that open parts of loops, and pots for adjustments, and none are mentioned in any manual. The "joys" of working on older gear!

Steve

WB0DBS

?

On Oct 16, 2015, at 10:47 AM, 'Peter' bunge@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?
Has anyone noticed that boards in HP 8350 plug-ins have part numbers different from the plug-in model?
My 83592 has two boards, A6 and A7, that have part numbers starting with 83595-x. The others start 83592-x.
?
I know that replacing the A6 board (83595-60106) with a good one (83592-60106) gets the plug-in working, even with the 83595-x A7 board.
?
On the bad A6 board I have found that a pot (R63, SRD bias) was missing and the Band 0 jumper was in the B1 position. The board also has two extra pots which are not shown on the schematic or component location. There are seven single turn pots on the top left, viewed from component side. They are shown in the 83595 manual. Did someone try to get it running with the board from a 83595 (0.01 to 26.5 GHz) plug-in?
I need to look carefully at every component. The 60106 in the number is the same (83592-60106) and the boards look identical but I’m sure there are component differences as I have found. I do not believe that this is the original board for the plug-in.
?
I have seen instruments put together with odd parts before. I have an HP8656A chassis that is part 8656A and part 8657A inside. I gave up troubleshooting when I discovered this. This is a very dishonest practice to do this and sell the items as-is, for parts, etc.
?
?

L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.

Re: HP 83592B hangs 8350B sweeper

#71855

X = horizontal axis
Y = vertical
There is no sweep, no trigger : the "sweep" results from the ramp applied to the horizontal deflection amplifier. X v. Y exits almost only on analog scopes (1741A on the 83592X manual)
--------------------------------------------

Show quoted text

On Sun, 10/18/15, 'Bill Lauchlan' bill.lauchlan@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

 Subject: RE: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper
 To: hp_agilent_equipment@...
 Date: Sunday, October 18, 2015, 3:03 AM


 ?









       I think A vs B means
 like an X-Y Plotter. You probably connect a Sweep Output
 Ramp to “B” and then some other Test Point to “A”.
 Rgds Bill Lauchlan ?From:
 hp_agilent_equipment@...
 [mailto:hp_agilent_equipment@...]
 Sent: Saturday, October 17, 2015 7:48
 PM
 To:
 hp_agilent_equipment@...
 Subject: RE: [hp_agilent_equipment] HP
 83592B hangs 8350B sweeper ?? Has anyone done a
 calibration on one of these plug-ins?Step 20 in
 adjustments: What does A vs B mode on an oscilloscope mean?
 I think HP means trigger on B and look at A ??(A + B or A
 – B will not work. The waveforms are completely different
 time/div and shapes)A6-TP8 does not have
 positive sweeps as shown. They go negative from 0 to -10v.
 Step 22: A6R37 will
 not affect TP8 an far as I can see.Am I missing
 something??From: hp_agilent_equipment@...
 [mailto:hp_agilent_equipment@...]

 Sent: October-17-15 5:54 PM
 To: hp_agilent_equipment@...
 Subject: RE: [hp_agilent_equipment] HP
 83592B hangs 8350B sweeper?? GREAT PROGRESS!Thanks Steve, you are
 quite correct. My A7 board is marked 83595 and works in this
 83592 plug-in.However I suspected that
 the A6 board that was causing all the trouble was actually
 from an 83595 not an 83592. I removed the 4L and 4H pots,
 installed the R63 pot, moved the Band jumper, ?and
 concentrated on the Sweep Control and Bandswitch
 circuits.The A3 SW1
 forces the signals to go through the variable gain amplifier
 for troubleshooting. Using this setting I could sweep band 0
 but was finding that the TP7 signal was going positive by
 2.4 volts. It should start at 0v and go negative to -10v
 max. There was an offset in the variable gain amplifier! I
 had also noticed that the gain seemed high. The schematics
 showed the gain resistors to be the same as the ones on the
 bad A6 board but they were different from the ones on the
 good A6 board. The parts list agreed with the resistors on
 the good A6 board so I assumed them to be correct. This was
 not the first error on the schematics I had found.Troubleshooting: Set sweep
 from 1 MHz to 1.1 MHz so TP5 is essentially at 0v. Check TP1
 (BandSw DAC O/P) is 1.195v on good A6 and 1.194 on bad A6.
 So far so good. Check U5-6 is -10.05v on good A6 but is?
 -12.73v on bad board. TP7 is 0v on the good A6 but is +2.4v
 on the bad board. Conclusion: the gain is too high and is
 tripping U14 in the Bandswitch Comparator.Change all 4 gain
 resistors:R29????????
 B0?????????? was 109.73k??????? change to
 82.541k (TP7 is now 0v with the above test)R27????????
 B1?????????? was 57.014k??????? change to
 42.884kR25????????
 B2?????????? was 40.423k??????? change to
 30.423kR23????????
 B3????????? was 40.423k??????? change to
 30.423kNow the
 plug-in sweeps from 0.01 to 20 GHz and the INSTR PRESET no
 longer hangs the 8350B.Conclusion: The A6 board
 was from an HP 83595. I can now proceed with the calibration
 bu expect some problems because the resistors I used were
 1%, not 0.1%, and are not the exact values. I may not have
 enough range of adjustment. I may also run into problems in
 the SRD and PIN diode bias circuits because of component
 values.Some of the
 analog switches are normally closed (PMI SW06) but are shown
 open on the schematic. U2A pins 1 & 2 are switched,
 U2A-2 goes to U13-11.Peter.??From: hp_agilent_equipment@...
 [mailto:hp_agilent_equipment@...]

 Sent: October-16-15 12:10 PM
 To: hp_agilent_equipment@...
 Subject: Re: [hp_agilent_equipment] HP
 83592B hangs 8350B sweeper?? Peter,?I have an 83594A and an
 83595A wth boards that have mismatched part numbers so it
 may not have been anything nefarious but if so its
 contagious! There are a couple of boards that don't
 match any of the manuals I've been able to find, and
 there are switches that open parts of loops, and pots for
 adjustments, and none are mentioned in any manual. The
 "joys" of working on older gear!

 SteveWB0DBS??
 On Oct 16,
 2015, at 10:47 AM, 'Peter' bunge@...
 [hp_agilent_equipment] <hp_agilent_equipment@...>
 wrote:? Has anyone noticed that boards in HP
 8350 plug-ins have part numbers different from the plug-in
 model?My 83592 has two boards, A6 and A7,
 that have part numbers starting with 83595-x. The others
 start 83592-x.?I know that replacing the A6 board
 (83595-60106) with a good one (83592-60106) gets the plug-in
 working, even with the 83595-x A7 board.?On the bad A6 board I have found that
 a pot (R63, SRD bias) was missing and the Band 0 jumper was
 in the B1 position. The board also has two extra pots which
 are not shown on the schematic or component location. There
 are seven single turn pots on the top left, viewed from
 component side. They are shown in the 83595 manual. Did
 someone try to get it running with the board from a 83595
 (0.01 to 26.5 GHz) plug-in? I need to look carefully at every
 component. The 60106 in the number is the same (83592-60106)
 and the boards look identical but I’m sure there are
 component differences as I have found. I do not believe that
 this is the original board for the plug-in.?I have seen instruments put together
 with odd parts before. I have an HP8656A chassis that is
 part 8656A and part 8657A inside. I gave up troubleshooting
 when I discovered this. This is a very dishonest practice to
 do this and sell the items as-is, for parts,
 etc.??






     



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Re: HP 83592B hangs 8350B sweeper

Bill Lauchlan

#71854

开云体育

I think A vs B means like an X-Y Plotter. You probably connect a Sweep Output Ramp to “B” and then some other Test Point to “A”. Rgds Bill Lauchlan

?

Show quoted text

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: Saturday, October 17, 2015 7:48 PM
To: hp_agilent_equipment@...
Subject: RE: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

Has anyone done a calibration on one of these plug-ins?

Step 20 in adjustments: What does A vs B mode on an oscilloscope mean? I think HP means trigger on B and look at A ??(A + B or A – B will not work. The waveforms are completely different time/div and shapes)

A6-TP8 does not have positive sweeps as shown. They go negative from 0 to -10v.

Step 22: A6R37 will not affect TP8 an far as I can see.

Am I missing something?

?

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: October-17-15 5:54 PM
To: hp_agilent_equipment@...
Subject: RE: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

GREAT PROGRESS!

Thanks Steve, you are quite correct. My A7 board is marked 83595 and works in this 83592 plug-in.

However I suspected that the A6 board that was causing all the trouble was actually from an 83595 not an 83592. I removed the 4L and 4H pots, installed the R63 pot, moved the Band jumper, ?and concentrated on the Sweep Control and Bandswitch circuits.

The A3 SW1 forces the signals to go through the variable gain amplifier for troubleshooting. Using this setting I could sweep band 0 but was finding that the TP7 signal was going positive by 2.4 volts. It should start at 0v and go negative to -10v max. There was an offset in the variable gain amplifier! I had also noticed that the gain seemed high. The schematics showed the gain resistors to be the same as the ones on the bad A6 board but they were different from the ones on the good A6 board. The parts list agreed with the resistors on the good A6 board so I assumed them to be correct. This was not the first error on the schematics I had found.

Troubleshooting: Set sweep from 1 MHz to 1.1 MHz so TP5 is essentially at 0v. Check TP1 (BandSw DAC O/P) is 1.195v on good A6 and 1.194 on bad A6. So far so good. Check U5-6 is -10.05v on good A6 but is? -12.73v on bad board. TP7 is 0v on the good A6 but is +2.4v on the bad board. Conclusion: the gain is too high and is tripping U14 in the Bandswitch Comparator.

Change all 4 gain resistors:

R29???????? B0?????????? was 109.73k??????? change to 82.541k (TP7 is now 0v with the above test)

R27???????? B1?????????? was 57.014k??????? change to 42.884k

R25???????? B2?????????? was 40.423k??????? change to 30.423k

R23???????? B3????????? was 40.423k??????? change to 30.423k

Now the plug-in sweeps from 0.01 to 20 GHz and the INSTR PRESET no longer hangs the 8350B.

Conclusion: The A6 board was from an HP 83595. I can now proceed with the calibration bu expect some problems because the resistors I used were 1%, not 0.1%, and are not the exact values. I may not have enough range of adjustment. I may also run into problems in the SRD and PIN diode bias circuits because of component values.

Some of the analog switches are normally closed (PMI SW06) but are shown open on the schematic. U2A pins 1 & 2 are switched, U2A-2 goes to U13-11.

Peter.

?

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: October-16-15 12:10 PM
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

Peter,

?

I have an 83594A and an 83595A wth boards that have mismatched part numbers so it may not have been anything nefarious but if so its contagious! There are a couple of boards that don't match any of the manuals I've been able to find, and there are switches that open parts of loops, and pots for adjustments, and none are mentioned in any manual. The "joys" of working on older gear!

Steve

WB0DBS

?

On Oct 16, 2015, at 10:47 AM, 'Peter' bunge@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?
Has anyone noticed that boards in HP 8350 plug-ins have part numbers different from the plug-in model?
My 83592 has two boards, A6 and A7, that have part numbers starting with 83595-x. The others start 83592-x.
?
I know that replacing the A6 board (83595-60106) with a good one (83592-60106) gets the plug-in working, even with the 83595-x A7 board.
?
On the bad A6 board I have found that a pot (R63, SRD bias) was missing and the Band 0 jumper was in the B1 position. The board also has two extra pots which are not shown on the schematic or component location. There are seven single turn pots on the top left, viewed from component side. They are shown in the 83595 manual. Did someone try to get it running with the board from a 83595 (0.01 to 26.5 GHz) plug-in?
I need to look carefully at every component. The 60106 in the number is the same (83592-60106) and the boards look identical but I’m sure there are component differences as I have found. I do not believe that this is the original board for the plug-in.
?
I have seen instruments put together with odd parts before. I have an HP8656A chassis that is part 8656A and part 8657A inside. I gave up troubleshooting when I discovered this. This is a very dishonest practice to do this and sell the items as-is, for parts, etc.
?
?

Re: HP 83592B hangs 8350B sweeper

#71853

开云体育

Has anyone done a calibration on one of these plug-ins?

Step 20 in adjustments: What does A vs B mode on an oscilloscope mean? I think HP means trigger on B and look at A ??(A + B or A – B will not work. The waveforms are completely different time/div and shapes)

A6-TP8 does not have positive sweeps as shown. They go negative from 0 to -10v.

Step 22: A6R37 will not affect TP8 an far as I can see.

Am I missing something?

?

Show quoted text

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: October-17-15 5:54 PM
To: hp_agilent_equipment@...
Subject: RE: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

GREAT PROGRESS!

Thanks Steve, you are quite correct. My A7 board is marked 83595 and works in this 83592 plug-in.

However I suspected that the A6 board that was causing all the trouble was actually from an 83595 not an 83592. I removed the 4L and 4H pots, installed the R63 pot, moved the Band jumper, ?and concentrated on the Sweep Control and Bandswitch circuits.

The A3 SW1 forces the signals to go through the variable gain amplifier for troubleshooting. Using this setting I could sweep band 0 but was finding that the TP7 signal was going positive by 2.4 volts. It should start at 0v and go negative to -10v max. There was an offset in the variable gain amplifier! I had also noticed that the gain seemed high. The schematics showed the gain resistors to be the same as the ones on the bad A6 board but they were different from the ones on the good A6 board. The parts list agreed with the resistors on the good A6 board so I assumed them to be correct. This was not the first error on the schematics I had found.

Troubleshooting: Set sweep from 1 MHz to 1.1 MHz so TP5 is essentially at 0v. Check TP1 (BandSw DAC O/P) is 1.195v on good A6 and 1.194 on bad A6. So far so good. Check U5-6 is -10.05v on good A6 but is? -12.73v on bad board. TP7 is 0v on the good A6 but is +2.4v on the bad board. Conclusion: the gain is too high and is tripping U14 in the Bandswitch Comparator.

Change all 4 gain resistors:

R29???????? B0?????????? was 109.73k??????? change to 82.541k (TP7 is now 0v with the above test)

R27???????? B1?????????? was 57.014k??????? change to 42.884k

R25???????? B2?????????? was 40.423k??????? change to 30.423k

R23???????? B3????????? was 40.423k??????? change to 30.423k

Now the plug-in sweeps from 0.01 to 20 GHz and the INSTR PRESET no longer hangs the 8350B.

Conclusion: The A6 board was from an HP 83595. I can now proceed with the calibration bu expect some problems because the resistors I used were 1%, not 0.1%, and are not the exact values. I may not have enough range of adjustment. I may also run into problems in the SRD and PIN diode bias circuits because of component values.

Some of the analog switches are normally closed (PMI SW06) but are shown open on the schematic. U2A pins 1 & 2 are switched, U2A-2 goes to U13-11.

Peter.

?

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: October-16-15 12:10 PM
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

Peter,

?

I have an 83594A and an 83595A wth boards that have mismatched part numbers so it may not have been anything nefarious but if so its contagious! There are a couple of boards that don't match any of the manuals I've been able to find, and there are switches that open parts of loops, and pots for adjustments, and none are mentioned in any manual. The "joys" of working on older gear!

Steve

WB0DBS

?

On Oct 16, 2015, at 10:47 AM, 'Peter' bunge@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?
Has anyone noticed that boards in HP 8350 plug-ins have part numbers different from the plug-in model?
My 83592 has two boards, A6 and A7, that have part numbers starting with 83595-x. The others start 83592-x.
?
I know that replacing the A6 board (83595-60106) with a good one (83592-60106) gets the plug-in working, even with the 83595-x A7 board.
?
On the bad A6 board I have found that a pot (R63, SRD bias) was missing and the Band 0 jumper was in the B1 position. The board also has two extra pots which are not shown on the schematic or component location. There are seven single turn pots on the top left, viewed from component side. They are shown in the 83595 manual. Did someone try to get it running with the board from a 83595 (0.01 to 26.5 GHz) plug-in?
I need to look carefully at every component. The 60106 in the number is the same (83592-60106) and the boards look identical but I’m sure there are component differences as I have found. I do not believe that this is the original board for the plug-in.
?
I have seen instruments put together with odd parts before. I have an HP8656A chassis that is part 8656A and part 8657A inside. I gave up troubleshooting when I discovered this. This is a very dishonest practice to do this and sell the items as-is, for parts, etc.
?
?

Re: HP 83592B hangs 8350B sweeper

#71852

开云体育

GREAT PROGRESS!

Thanks Steve, you are quite correct. My A7 board is marked 83595 and works in this 83592 plug-in.

However I suspected that the A6 board that was causing all the trouble was actually from an 83595 not an 83592. I removed the 4L and 4H pots, installed the R63 pot, moved the Band jumper, ?and concentrated on the Sweep Control and Bandswitch circuits.

The A3 SW1 forces the signals to go through the variable gain amplifier for troubleshooting. Using this setting I could sweep band 0 but was finding that the TP7 signal was going positive by 2.4 volts. It should start at 0v and go negative to -10v max. There was an offset in the variable gain amplifier! I had also noticed that the gain seemed high. The schematics showed the gain resistors to be the same as the ones on the bad A6 board but they were different from the ones on the good A6 board. The parts list agreed with the resistors on the good A6 board so I assumed them to be correct. This was not the first error on the schematics I had found.

Troubleshooting: Set sweep from 1 MHz to 1.1 MHz so TP5 is essentially at 0v. Check TP1 (BandSw DAC O/P) is 1.195v on good A6 and 1.194 on bad A6. So far so good. Check U5-6 is -10.05v on good A6 but is? -12.73v on bad board. TP7 is 0v on the good A6 but is +2.4v on the bad board. Conclusion: the gain is too high and is tripping U14 in the Bandswitch Comparator.

Change all 4 gain resistors:

R29???????? B0?????????? was 109.73k??????? change to 82.541k (TP7 is now 0v with the above test)

R27???????? B1?????????? was 57.014k??????? change to 42.884k

R25???????? B2?????????? was 40.423k??????? change to 30.423k

R23???????? B3????????? was 40.423k??????? change to 30.423k

Now the plug-in sweeps from 0.01 to 20 GHz and the INSTR PRESET no longer hangs the 8350B.

Conclusion: The A6 board was from an HP 83595. I can now proceed with the calibration bu expect some problems because the resistors I used were 1%, not 0.1%, and are not the exact values. I may not have enough range of adjustment. I may also run into problems in the SRD and PIN diode bias circuits because of component values.

Some of the analog switches are normally closed (PMI SW06) but are shown open on the schematic. U2A pins 1 & 2 are switched, U2A-2 goes to U13-11.

Peter.

?

Show quoted text

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: October-16-15 12:10 PM
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] HP 83592B hangs 8350B sweeper

?

Peter,

?

I have an 83594A and an 83595A wth boards that have mismatched part numbers so it may not have been anything nefarious but if so its contagious! There are a couple of boards that don't match any of the manuals I've been able to find, and there are switches that open parts of loops, and pots for adjustments, and none are mentioned in any manual. The "joys" of working on older gear!

Steve

WB0DBS

?

On Oct 16, 2015, at 10:47 AM, 'Peter' bunge@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?
Has anyone noticed that boards in HP 8350 plug-ins have part numbers different from the plug-in model?
My 83592 has two boards, A6 and A7, that have part numbers starting with 83595-x. The others start 83592-x.
?
I know that replacing the A6 board (83595-60106) with a good one (83592-60106) gets the plug-in working, even with the 83595-x A7 board.
?
On the bad A6 board I have found that a pot (R63, SRD bias) was missing and the Band 0 jumper was in the B1 position. The board also has two extra pots which are not shown on the schematic or component location. There are seven single turn pots on the top left, viewed from component side. They are shown in the 83595 manual. Did someone try to get it running with the board from a 83595 (0.01 to 26.5 GHz) plug-in?
I need to look carefully at every component. The 60106 in the number is the same (83592-60106) and the boards look identical but I’m sure there are component differences as I have found. I do not believe that this is the original board for the plug-in.
?
I have seen instruments put together with odd parts before. I have an HP8656A chassis that is part 8656A and part 8657A inside. I gave up troubleshooting when I discovered this. This is a very dishonest practice to do this and sell the items as-is, for parts, etc.
?
?

Re: off topic old tube tester

#71851

开云体育

I don't have anything that would help, but there is a Yahoo forum named "TubeTesters" where you might find some help.

DaveD

On 10/16/2015 11:09 PM, Ken Chalfant kpchalfant@... [hp_agilent_equipment] wrote:

Show quoted text

?

Greetings,

Kindly allow me to ask for assistance regarding a very loosely related question. I just acquired a 57 year old Shell Test-O-Matic tube tester for a young friend who restores old trucks and is learning how to repair and rebuild the original AM radios.

The tube tester has a lid mounted “set-up” chart dated June 1958, mostly in legible condition.

Does anyone have additional or supplemental tube test charts for this generation of Test-O-Matic tube tester you are willing to share, copy, or sell?

Thanks very much for your time and bandwidth.

Regards,

Ken

Re: off topic old tube tester

#71850

Hey Ken,

I have a "U-Test-M" that I restored a while back.? It's documented . I'm not sure how similar it is or if the chart could be used.? I can take some pictures of my chart and see if it aligns with the Test-O-Matic.

Gary

off topic old tube tester

#71849

Greetings,

Kindly allow me to ask for assistance regarding a very loosely related question.  I just acquired a 57 year old Shell Test-O-Matic tube tester for a young friend who restores old trucks and is learning how to repair and rebuild the original AM radios.

The tube tester has a lid mounted “set-up” chart dated June 1958, mostly in legible condition.

Does anyone have additional or supplemental tube test charts for this generation of Test-O-Matic tube tester you are willing to share, copy, or sell?

Thanks very much for your time and bandwidth.

Regards,

Ken

Re: HP 70820A connectors

#71848

I had the same problem a while back - the adapters cost more than whole scope, and I couldn't test to see if it was any good without putting in a proper input signal. I asked here, and someone steered me to a lady that was selling all kinds of microwave cables on ebay. As I recall, I found some short jumper cables there that had 2.4 mm on one end, and SMA (or maybe 2.92 - SMA compatible) on the other, for about $15 each. It was not quite the same as having the precision barrel adapters, but good enough for my needs, at much lower cost. The cheapest barrel types I found at the time were about $100 each.

Just keep asking here - someone knew the right place to go (if still there) - or search the archives for 70820A, and maybe that thread will show up. It's rare enough that there shouldn't be much chaff to sort out. It would have been from about two or three years ago, I think.

Ed

Re: HP 70820A connectors

#71847

Thanks guys for the various replies.

I'm was almost sure these are 2.4mm connectors (and not 2.92) because the HP literature for the 70820A refers to needing APC-2.4mm adaptors, plus they don't look like they will mate with SMA connectors (I didn't want to "force" one in and wreck it, so I'm not totally sure!). I browsed all the 70820A literature I could find, but didn't spot a definitive statement of what the front panel connectors were (perhaps there are options, I don't know).

Perhaps as Dave Kirby suggests, I'll try making a low offer on a couple of adaptors to SMA, and see if I get anywhere.

Steve G4KNZ.

Re: HP 70820A connectors

#71846

Dave,

You may already know the history of the NMD, but for those that don't, the NMD connector (Network Measurements Division) was HP's solution to stabilize test port cables on various test sets. With good test port cables, NMD test port connectors, and the anti-rotation clamps (08515-60003 if memory serves me) you can get pretty consistent results. I agree with you that NMD will properly mate with standard connectors but I've seen the results of standard connectors screwed into test ports and without extreme care (which I take for granted everyone exercises with precision connectors, right :0)) the results are usually pretty poor repeatability over a series of measurements and possibly a telltale dip in response at higher frequencies. I didn't intend my answer to mean it couldn't be done, just that there are risks and the NMD was designed to help minimize them. For that you usually pay a premium.

Steve

WB0DBS

On Oct 16, 2015, at 3:38 PM, "Dave McGuire Mcguire@... [hp_agilent_equipment]" <hp_agilent_equipment@...> wrote:

Show quoted text

?

On 10/16/2015 03:51 PM, Steve Steve-Krull@... [hp_agilent_equipment]
wrote:
> The NMD is a special test port connector, not a standard connector. Have
> a look at the Maury website for pictures. You might be able to fit a
> standard connector to a test port but I wouldn't guarantee the accuracy
> or reliability of the results. I agree 500 USD per NMD connector is a
> big chunk of money; and cable sets are really pricy. You might be able
> to find a pair of connectors at a more reasonable price but you'll find
> that precision connectors demand a higher price. Even if you stop at
> 26.5G you're still faced with getting from the NMD test ports to 3.5mm
> or SMA. I recently passed on a 70820A on eBay for exactly that reason.
> Beware the cheap inter-series adapters if you're after any sort of
> repeatability and reliability.

The NMD connectors are "supersets" of standard connectors, like 3.5mm,
2.4mm, etc. They are designed to be entirely compatible with them, and
are very frequently used in that environment.

-Dave

--
Dave McGuire, AK4HZ
New Kensington, PA

Re: HP 70820A connectors

#71845

I had forgotten, yes, they are 2.4mm. The rest of my post still stands. You cannot interconnect SMA with them, you need an adapter. I went through this when I had to replace the (missing) 2.4mm NDM's on my 70820.

On Fri, Oct 16, 2015 at 5:06 PM, 'Dr. David Kirkby - Kirkby Microwave Ltd ' drkirkby@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

Show quoted text

?

On 10/16/15 08:44 PM, Bob Bownes bownes@... [hp_agilent_equipment] wrote:
> They are 2.92mm. The easiest thing to get is 2.92mm to SMA adapters, but
> they are quite pricey at about $100 each.
>
> You can order 2.92mm to *.* test port cables, but, again, expect to pay
> quite a bit. Sometimes you see them on ebay for about $250-$300 each for
> 2.92mm to N or SMA.

I don't know what connectors these, as I don't have one, but I was lead to
believe by someone else they are 2.4 mm. If 2.4 mm as the author states, then
they will not mate to SMA. But if 2.92 mm they will mate to SMA. But of course
they wont have the performance. Also 2.92 mm is very fragile - much more so than
2.4 or 3.5 mm.

One of my VNAs has 3.5 mm NMD connectors on it. I managed to pick up a pair of
adapters to N for about $150, and much the same for adapters to 3.5 mm. I do
also have the proper test port cables, but they are serious money.

Sure you see NMD adapters on eBay for stupid money, but it is not hard to buy
them at a lot less. Many of the people asking $500 will probably take $100-$200
for them if you ask.

Dave

>
>
>
> On Fri, Oct 16, 2015 at 3:14 PM, steve@...
> [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
>
>>
>> I just got hold of a 70820A microwave transition analyzer, and need either
>> cables or adaptors for the two RF ports. As I understand it, these are
>> APC-2.4 connectors, also known as NMD 2.4mm? Is that correct, two names for
>> the same connector, or is there some difference?
>>
>>
>> I just tried to find some adaptors, a quick look on ePay, one adaptor is
>> coming up at around $500 US, so I'd be spending more on the adaptors than I
>> paid for the whole unit. Anyone know of a more affordable source? I really
>> only want to go up to 26.5GHz, and don't really care about the perfomance
>> any higher.
>>
>>
>>

--
Dr. David Kirkby Ph.D CEng MIET
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK.
Registered in England and Wales, company number 08914892.

Tel: 07910 441670 / +44 7910 441670 (0900 to 2100 GMT only please)

[Non-text portions of this message have been removed]

Re: HP 70820A connectors

#71844

开云体育

The 70820A uses male 2.4 mm connectors.? I don't think I've seen any with 2.92.

?

For interfacing with 3.5mm or (good-quality) SMA M-M cables, I use A350F240F adapters from "rfextra" on eBay.? These were sold for a while at http://cgi.ebay.com/160715492551 for "only" $100 each, but it looks like they're out of stock at the moment.

?

-- john, KE5FX

?

Show quoted text

From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]
Sent: Friday, October 16, 2015 12:45 PM
To: hp_agilent_equipment@...
Subject: Re: [hp_agilent_equipment] HP 70820A connectors

?

They are 2.92mm. The easiest thing to get is 2.92mm to SMA adapters, but they are quite pricey at about $100 each.

You can order 2.92mm to *.* test port cables, but, again, expect to pay quite a bit. Sometimes you see them on ebay for about $250-$300 each for 2.92mm to N or SMA.

Re: HP 70820A connectors

Dr. David Kirkby - Kirkby Microwave Ltd

#71843

On 10/16/15 08:44 PM, Bob Bownes bownes@... [hp_agilent_equipment] wrote:
They are 2.92mm. The easiest thing to get is 2.92mm to SMA adapters, but
they are quite pricey at about $100 each.

You can order 2.92mm to *.* test port cables, but, again, expect to pay
quite a bit. Sometimes you see them on ebay for about $250-$300 each for
2.92mm to N or SMA.I don't know what connectors these, as I don't have one, but I was lead to 
believe by someone else they are 2.4 mm. If 2.4 mm as the author states, then 
they will not mate to SMA. But if 2.92 mm they will mate to SMA. But of course 
they wont have the performance. Also 2.92 mm is very fragile - much more so than 
2.4 or 3.5 mm.

One of my VNAs has 3.5 mm NMD connectors on it. I managed to pick up a pair of 
adapters to N for about $150, and much the same for adapters to 3.5 mm. I do 
also have the proper test port cables, but they are serious money.

Sure you see NMD adapters on eBay for stupid money, but it is not hard to buy 
them at a lot less. Many of the people asking $500 will probably take $100-$200  
for them if you ask.

Dave




On Fri, Oct 16, 2015 at 3:14 PM, steve@...
[hp_agilent_equipment] <hp_agilent_equipment@...> wrote:


I just got hold of a 70820A microwave transition analyzer, and need either
cables or adaptors for the two RF ports. As I understand it, these are
APC-2.4 connectors, also known as NMD 2.4mm? Is that correct, two names for
the same connector, or is there some difference?


I just tried to find some adaptors, a quick look on ePay, one adaptor is
coming up at around $500 US, so I'd be spending more on the adaptors than I
paid for the whole unit. Anyone know of a more affordable source? I really
only want to go up to 26.5GHz, and don't really care about the perfomance
any higher.



-- 
Dr. David Kirkby Ph.D CEng MIET
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK.
Registered in England and Wales, company number 08914892.

Tel: 07910 441670 / +44 7910 441670 (0900 to 2100 GMT only please)

Re: HP 70820A connectors

#71842

On 10/16/2015 03:51 PM, Steve Steve-Krull@... [hp_agilent_equipment]
wrote:
The NMD is a special test port connector, not a standard connector. Have
a look at the Maury website for pictures. You might be able to fit a
standard connector to a test port but I wouldn't guarantee the accuracy
or reliability of the results. I agree 500 USD per NMD connector is a
big chunk of money; and cable sets are really pricy. You might be able
to find a pair of connectors at a more reasonable price but you'll find
that precision connectors demand a higher price. Even if you stop at
26.5G you're still faced with getting from the NMD test ports to 3.5mm
or SMA. I recently passed on a 70820A on eBay for exactly that reason.
Beware the cheap inter-series adapters if you're after any sort of
repeatability and reliability.  The NMD connectors are "supersets" of standard connectors, like 3.5mm,
2.4mm, etc.  They are designed to be entirely compatible with them, and
are very frequently used in that environment.

               -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA

Re: HP 70820A connectors

#71841

Steve,

The NMD is a special test port connector, not a standard connector. Have a look at the Maury website for pictures. You might be able to fit a standard connector to a test port but I wouldn't guarantee the accuracy or reliability of the results. I agree 500 USD per NMD connector is a big chunk of money; and cable sets are really pricy. You might be able to find a pair of connectors at a more reasonable price but you'll find that precision connectors demand a higher price. Even if you stop at 26.5G you're still faced with getting from the NMD test ports to 3.5mm or SMA. I recently passed on a 70820A on eBay for exactly that reason. Beware the cheap inter-series adapters if you're after any sort of repeatability and reliability.

Steve K.

Show quoted text

On Oct 16, 2015, at 2:14 PM, "steve@... [hp_agilent_equipment]" <hp_agilent_equipment@...> wrote:

?

I just got hold of a 70820A microwave transition analyzer, and need either cables or adaptors for the two RF ports. As I understand it, these are APC-2.4 connectors, also known as NMD 2.4mm? Is that correct, two names for the same connector, or is there some difference?

I just tried to find some adaptors, a quick look on ePay, one adaptor is coming up at around $500 US, so I'd be spending more on the adaptors than I paid for the whole unit. Anyone know of a more affordable source? I really only want to go up to 26.5GHz, and don't really care about the perfomance any higher.

Re: HP 70820A connectors

#71840

They are 2.92mm. The easiest thing to get is 2.92mm to SMA adapters, but they are quite pricey at about $100 each.

You can order 2.92mm to *.* test port cables, but, again, expect to pay quite a bit. Sometimes you see them on ebay for about $250-$300 each for 2.92mm to N or SMA.

Show quoted text

On Fri, Oct 16, 2015 at 3:14 PM, steve@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?

I just got hold of a 70820A microwave transition analyzer, and need either cables or adaptors for the two RF ports. As I understand it, these are APC-2.4 connectors, also known as NMD 2.4mm? Is that correct, two names for the same connector, or is there some difference?

I just tried to find some adaptors, a quick look on ePay, one adaptor is coming up at around $500 US, so I'd be spending more on the adaptors than I paid for the whole unit. Anyone know of a more affordable source? I really only want to go up to 26.5GHz, and don't really care about the perfomance any higher.

HP 70820A connectors

#71839

I just got hold of a 70820A microwave transition analyzer, and need either cables or adaptors for the two RF ports. As I understand it, these are APC-2.4 connectors, also known as NMD 2.4mm? Is that correct, two names for the same connector, or is there some difference?

I just tried to find some adaptors, a quick look on ePay, one adaptor is coming up at around $500 US, so I'd be spending more on the adaptors than I paid for the whole unit. Anyone know of a more affordable source? I really only want to go up to 26.5GHz, and don't really care about the perfomance any higher.

Re: HP 83592B hangs 8350B sweeper

#71838

开云体育

Peter,

I have an 83594A and an 83595A wth boards that have mismatched part numbers so it may not have been anything nefarious but if so its contagious! There are a couple of boards that don't match any of the manuals I've been able to find, and there are switches that open parts of loops, and pots for adjustments, and none are mentioned in any manual. The "joys" of working on older gear!

Steve

WB0DBS

Show quoted text

On Oct 16, 2015, at 10:47 AM, 'Peter' bunge@... [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:

?

Has anyone noticed that boards in HP 8350 plug-ins have part numbers different from the plug-in model?
My 83592 has two boards, A6 and A7, that have part numbers starting with 83595-x. The others start 83592-x.
?
I know that replacing the A6 board (83595-60106) with a good one (83592-60106) gets the plug-in working, even with the 83595-x A7 board.
?
On the bad A6 board I have found that a pot (R63, SRD bias) was missing and the Band 0 jumper was in the B1 position. The board also has two extra pots which are not shown on the schematic or component location. There are seven single turn pots on the top left, viewed from component side. They are shown in the 83595 manual. Did someone try to get it running with the board from a 83595 (0.01 to 26.5 GHz) plug-in?
I need to look carefully at every component. The 60106 in the number is the same (83592-60106) and the boards look identical but I’m sure there are component differences as I have found. I do not believe that this is the original board for the plug-in.
?
I have seen instruments put together with odd parts before. I have an HP8656A chassis that is part 8656A and part 8657A inside. I gave up troubleshooting when I discovered this. This is a very dishonest practice to do this and sell the items as-is, for parts, etc.
?
?