My HP8340B , even if the level indicator say the right level end no unleveled annunciator appear , the real RF output is unstable. Sweeping at some frequencies the power out goes unleveled , it happens in the 3 High band . Only some point and small range in the first high band increasing in second high band finally large portion of band in 3rd high band. The internal power detector and all its circuit works ok ,the out voltage that goes to the error amplifier and its corresponding reference level are ok. The ALC level sims working according to the specs. At a certain point of the ALC loop A26 Board a signal is taken out SDR BIAS CONT? using an OP Amp ( way the designer have set a test point at the inverting input and not to the output is a mystery¡.but this is useful for my investigation). This signal goes to board A24 and shaped using frequency info ( 2 times ) plus an exponential generator drives the SRD in order to allow a linear operation in the power range. What happens is that to SDR is driven in non linear zone ( reverse power vs SRD voltage increase) this leads what HP manual call SQEGGING , the output power become to be modulated ,the average continue to be ok so the equipment do not detect any malfunction and no unleveled light appears . Focusing at 22.5 GHz where this problem is more evident breaking the SRD line and driving externally the correct operation can be obtained increasing the SRD voltage ?at high power output ( see PDF Misure a 22 5 GHz) . Using this info I placed a circuit offset using the test point located at the inverting input of the OP Amp located in A26 board ( a pot using -10V one side and + 5.2V other side and 1 Mohm from the cursor to the inverting input ). Inserting the offset first ?disappear the instability in high band 1 then increasing the offset the problem of high band 2 at the end setting an offset at the out of the OP amp of 0.3 V all the band are ok . This could be a work around because at the end the equipment works . Due to this need of offset ( small in first High band medium in second high band and finally 0.3 V in 3rd band ) push me to think that is not a general ?offset? the problem but a shaping problem or an offset linked with the frequency . The A24 board makes this kind of job but looks a mess al potentiometers , can someone help me because that in the past entered in similar problem? Turning pots in random mode is not what I like !!! Regards Gianni IW1EPY ? ? ? It would be desirable to catalog those commands so they can be analyzed and further documented and eventually be used in creating some calibration routines that can be used by people ! Let me however render some words of caution :? Keysight/agilent has chosen the path of not to provide service software any longer for a very good reason and to put it simple its all about MONEY ! Used to service was purely auxiliary now it¡¯s a profit center , keysight wants to keep their service centers busy and they want to control end of life of their equipment , if the analyzer requires software to do adjustments and you don¡¯t have the software than you cant fix the unit period !? when it was still available the N7800A software was very expensive , If I remember correctly the framework was $7500 and then you had to pay for the different support modules separately , once you shilled out the $? you needed very specific test equipment which set you back another 100-200K depending on what you wanted to run ¡¡..? after a little while they stopped issuing licenses altogether and only made them available to big corporate self supporters ! Having said this keysight may not take kindly to the information becoming public and may undertake measures to deter the effort , therefore I strongly suggest not to use any techniques to extract the information that could be interpreted as reverse engineering or hacking ?
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From: [email protected] <[email protected]> On Behalf Of Sandra Carroll via groups.io
Sent: Sunday, June 5, 2022 8:37 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] ESA instrument adjustments - reverse engineering? Hi Kalle.
This is fantastic work.? ?
When I was working on hacking the E4407B one thing I was looking for was the SCPI commands but could never find them.
Did you find these on the E4407B or did you find them in the looking at N7800?files?
I really hope we can find a way to be able to do a cal.? personally I'd like to cal my TG as I think that it needs it?
If I can help on this I'm more than will.
Sandra
|
Re: HP 8116A woes with E42 error
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Re: HP8563E-Damaged red coax from A4 PCB-Is it easy to replace?
This red cable is approx 80cm long and travels between the A3 and A4 PCB's (located on the top stack of boards or folded out to the right). I have checked the continuity of the cable and it is OK.
I checked it by tack soldering four wires onto a couple of SMB connectors on one of the boards. I then plugged the cable into the sockets at both ends and used the continuity test on my multimeter to test the cable whilst I moved it around. There is NO sign of any breaks. So now I can proceed with reassembly. Thanks everyone for your help.
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Re: ESA instrument adjustments - reverse engineering
It would be desirable to catalog those commands so they can be analyzed and further documented and eventually be used in creating some calibration routines that can be used by people !
Let me however render some words of caution :?
Keysight/agilent has chosen the path of not to provide service software any longer for a very good reason and to put it simple its all about MONEY !
Used to service was purely auxiliary now it¡¯s a profit center , keysight wants to keep their service centers busy and they want to control end of life of their equipment , if the analyzer requires software to do adjustments and you don¡¯t
have the software than you cant fix the unit period !? when it was still available the N7800A software was very expensive , If I remember correctly the framework was $7500 and then you had to pay for the different support modules separately , once you shilled
out the $? you needed very specific test equipment which set you back another 100-200K depending on what you wanted to run ¡¡..? after a little while they stopped issuing licenses altogether and only made them available to big corporate self supporters !
Having said this keysight may not take kindly to the information becoming public and may undertake measures to deter the effort , therefore I strongly suggest not to use any techniques to extract the information that could be interpreted
as reverse engineering or hacking
?
toggle quoted message
Show quoted text
From: [email protected] < [email protected]>
On Behalf Of Sandra Carroll via groups.io
Sent: Sunday, June 5, 2022 8:37 PM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] ESA instrument adjustments - reverse engineering
?
Hi Kalle.
This is fantastic work.? ?
When I was working on hacking the E4407B one thing I was looking for was the SCPI commands but could never find them.
Did you find these on the E4407B or did you find them in the looking at N7800?files?
I really hope we can find a way to be able to do a cal.? personally I'd like to cal my TG as I think that it needs it?
If I can help on this I'm more than will.
Sandra
|
Re: ESA instrument adjustments - reverse engineering
Hi Sandra
I couldn't resist? though I'm pretty sure you are not related to me.? I am Robert Carroll and was raised starting in 1945 in East Point, GA.? I went to Georgia Tech through my Masters and thanks to the draft was inducted into the USAF and was assigned to intelligence work and development of false target repeaters to protect the B-52 bombers.? ?And there I was frequently using HP equipment at Wright Patterson Air Force Base. And though now an ancient one, I still use HP equipment in connection with my Ham Radio.
Robert Carroll (w2wg now in Cobb County, GA.)
Sent from my Verizon, Samsung Galaxy smartphone
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-------- Original message -------- From: Sandra Carroll <smgvbest@...> Date: 6/5/22 9:36 PM (GMT-05:00) Subject: Re: [HP-Agilent-Keysight-equipment] ESA instrument adjustments - reverse engineering
Hi Kalle. This is fantastic work.? ? When I was working on hacking the E4407B one thing I was looking for was the SCPI commands but could never find them. Did you find these on the E4407B or did you find them in the looking at N7800?files? I really hope we can find a way to be able to do a cal.? personally I'd like to cal my TG as I think that it needs it? If I can help on this I'm more than will. Sandra
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Re: ESA instrument adjustments - reverse engineering
Hi Kalle.
This is fantastic work.? ?
When I was working on hacking the E4407B one thing I was looking for was the SCPI commands but could never find them.
Did you find these on the E4407B or did you find them in the looking at N7800?files?
I really hope we can find a way to be able to do a cal.? personally I'd like to cal my TG as I think that it needs it?
If I can help on this I'm more than will.
Sandra
|
Re: The time-bomb in the HP 70700A digitizer
Has anyone replaced the battery in the hp 70700a and
? know:
a)
the battery specifications,? shape/size; ? &? the R&R installation procedure ?
{ without loosing the existing Pgm in Ram: obviously parallel install, but did HP have a defined procedure ? }
&
b)
the replacement battery part #,? from Mouser or Digikey ?
There is no reference to the word "battery" to be found in either of the Install, Op Man, Service Man, nor Pgm Man.
( HP Man #'s? 70700-90001, -90003, -90005, -90021 )
thank you,
rick
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Re: HP 8970B System Check
"Lothar baier" <Lothar@...> writes: ok first of the gain of this unit is not a hard specs but quantified as >xx , keep in mind that this is a noise figure testset that is used as part of a system and is calibrated out before measurements are performed ,? the 8971C has a wideband preamp in the signal path that is present for all measurement modes , the main purpose of this amp is to lower the system NF,? the amp has a spec of >20.5dB over the 10MHz-26GHz but since this a extremely wideband amplifer gain can vary quite a bit over the entire range , for SSB mode no additional parts are switched in so if you measure higher gain than anticipated than either somebody has messed with the unit and replaced either the amplifier with a replacement that has more gain or the attenuator is bad but i have seen very few attenuators that are showing lower attenuation than published usually attenuation goes higher ... Thanks so much Lothar, this is all immensely helpful. I performed the coarse calibration after setting the upper frequency limit to 18 GHz and the LO input power to 1 dBm since I have option 001. The calibration passed and I now see about 24 dB of gain in SSB3. That's a bit high but from your statement about the gain only being specified as a lower limit and varying, it sounds like this isn't an issue. I still see around 6 dB NF instead of 8-12 dB when performing the system check (step 16). I'm not entirely clear what noise figure it's measuring here; is this the combined test set + 8970B receiver NF? If so, maybe because the preamp gain is on the high side, the system noise figure is lower than expected. For SSB2 the signal is amplified 20dB then goes through a bandpass filter and a attenuator that improves matching before entering the mixer and then the IF amplifier ,
the lineup looks like this :? 20dB (RF Amp)-0.5dB (filter )-7dB (attenuator)-10dB(Mixer)+22dB (IF amplifier) = 24.5dB so your 24dB measurement is in line with what you should see ! This is missing the contribution from AT3 right? That would move the gain 6 dB lower. For SSB3 the equation looks similar but the filter loss is 3dB and the attenuator is 3dB instead of 7dB so you have 6dB instead of 7.5dB meaning your gain increases to 25.5dB !
Now a few caveats :? SSB2 and SSB3 use a mixer and the conversion loss of a mixer generally depends on the LO power ,? if you have a unit with LO amp than the typical LO power you should feed in the unit is 1dBm which after beein amplified by 10dB and then passed through some cables gives you about 10dBm LO power ,? if you apply a higher LO power the amplifier Pout increases until the amplifier starts compressing, this means that your conversion loss slightly improves at the risk that the power exceeds eventually damage level and the mixer sustains damage , if not then the amplifier will go into compression reducing the gain and Pout of the amplifier so the conversion gain of the mixer will increase as the lo power coming from the buffer amp starts dropping .......? so if your unit has the LO amplifier (option 001 or 001/002) make sure you keep your LO at or below 1dBm ,? if the unit does not have LO buffer amp than your LO should be typically around 7-10dB !
Last but not least keep in mind that the YIG filter has a bandwidth of only 10-30MHz , your 8970B has a fixed IF BW of 4MHz so if your filter does not track correctly you will be tuned on the flanks of the filter and your loss will increase significantly above the 3dB in the center of the passband , the fact that your gain increases when you tune your signal source shows this is what is happening here .
This is why you normally when you put together a system you perform the coarse and fine peaking procedure outlined in the manual and repeat it every now and then
i hope this helps It does, thank you. Matt
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16700A won't start graphical display
Hi,
After several years and a recent cross country move I need a logic analyzer again.? I tried my 16702B and it is DOA; the power supply is getting AC but won't start.
I then tried my 16700A.? The VGA display eventually came up with a screen with 8 yellow boxes on the bottom of which 3 had some text in them like "REMOTE", etc.? It looked like just a text display.
I then hooked up my laptop to the serial port and rebooted.? I got this (copyright stuff at the beginning deleted):
? ?#
? # # ? ? #### ? ? ?# ? ?# ? ? ? ###### ?# ? ?# ? #####
?# ? # ? # ? ?# ? ? # ? ?# ? ? ? # ? ? ? ## ? # ? ? #
# ? ? # ?# ? ? ? ? ?# ? ?# ? ? ? ##### ? # # ?# ? ? #
####### ?# ?### ? ? # ? ?# ? ? ? # ? ? ? # ?# # ? ? #
# ? ? # ?# ? ?# ? ? # ? ?# ? ? ? # ? ? ? # ? ## ? ? #
# ? ? # ? #### ? ? ?# ? ?###### ?###### ?# ? ?# ? ? #
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Logic Analysis System
httpd.conf file installed
/sbin/bcheckrc:
Checking for LVM volume groups and Activating (if any exist)
Volume group "/dev/vg00" has been successfully changed.
vxfs fsck: sanity check: root file system OK (mounted read/write)
/sbin/itemap: WARNING: An attempt to write keyboard mapping entries past
/sbin/itemap: the end of the buffer.? Further writes will be ignored.
Checking hfs file systems
/sbin/fsclean: /dev/vg00/lvol1 (mounted) ok
HFS file systems are OK, not running fsck
Checking vxfs file systems
/dev/vg00/lvol4 :
vxfs fsck: sanity check: root file system OK (mounted read/write)
/dev/vg00/lvol5 :
vxfs fsck: sanity check: /dev/vg00/lvol5 needs checking
log replay in progress
replay complete - marking super-block as CLEAN
/dev/vg00/lvol6 :
vxfs fsck: sanity check: /dev/vg00/lvol6 needs checking
log replay in progress
replay complete - marking super-block as CLEAN
Jul 07 01:07:11 auto_parms >> Checking network status.
Jul 07 01:07:11 auto_parms >> Network was disabled by boot scripts on previous boot.? Re-activating the network.
8/16/6 ? 0x001083B89AE4 0 ? UP ? ? ? lan0 ? ? DOWN ? 4 ? ETHER ? ? ?Yes ? ? 52
Jul 07 01:07:12 auto_parms >> /sbin/auto_parms, checking network for DHCP server (see /etc/auto_parms.log)
Jul 07 01:07:25 auto_parms >> DHCP Client Status: NO_REPLY_RECEIVED
? ? ?HP-UX Start-up in progress
? ? ?__________________________
? ? ?Mount file systems ................................ OK
? ? ?Setting hostname .................................. OK
? ? ?Enable auxiliary swap space ....................... OK
? ? ?Start syncer daemon ............................... OK
? ? ?Configure LAN interfaces .......................... OK
? ? ?Check LAN Status .................................. N/A
? ? ?Start Software Distributor agent daemon ........... OK
? ? ?Configuring all unconfigured software filesets .... OK
? ? ?List and/or clear temporary files ................. OK
? ? ?Clean up old log files ............................ OK
? ? ?Start system message logging daemon ............... OK
? ? ?Configure HP Ethernet interfaces .................. OK
? ? ?Configure HP 100BT interfaces ..................... N/A
? ? ?Configure LAN interfaces .......................... OK
? ? ?Start NFS core subsystem .......................... OK
? ? ?Start NFS client subsystem ........................ OK
? ? ?Start Internet services daemon .................... OK
? ? ?Cleaning up NIS client subsystem .................. OK
? ? ?Start NIS client subsystem ........................ OK
? ? ?Verifying NIS client subsystem .................... OK
? ? ?Starting kks daemon ............................... OK
? ? ?Start time synchronization ........................ N/A
? ? ?Start print spooler ............................... OK
? ? ?Start clock daemon ................................ OK
? ? ?Set X11 Device Configuration ...................... OK
? ? ?Start 16610A Processor Run Control daemon ......... OK
? ? ?Start httpd (Web Server) .......................... N/A
? ? ?Start NFS server subsystem ........................ OK
? ? ?Start Lmgrd daemon ................................ OK
The system is ready.
Starting Logic Analysis System ...
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
TERM = (hp)
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
Shutting down Logic Analyzer ...
Starting Logic Analysis System ...
Any ideas on how to get out of this mode?
Thanks,
Marc
|
Re: HP 8970B System Check
ok first of the gain of this unit is not a hard specs but quantified as >xx , keep in mind that this is a noise figure testset that is used as part of a system and is calibrated out before measurements are performed ,? the 8971C has a wideband preamp in the signal path that is present for all measurement modes , the main purpose of this amp is to lower the system NF,? the amp has a spec of >20.5dB over the 10MHz-26GHz but since this a extremely wideband amplifer gain can vary quite a bit over the entire range , for SSB mode no additional parts are switched in so if you measure higher gain than anticipated than either somebody has messed with the unit and replaced either the amplifier with a replacement that has more gain or the attenuator is bad but i have seen very few attenuators that are showing lower attenuation than published usually attenuation goes higher ...
For SSB2 the signal is amplified 20dB then goes through a bandpass filter and a attenuator that improves matching before entering the mixer and then the IF amplifier ,
the lineup looks like this :? 20dB (RF Amp)-0.5dB (filter )-7dB (attenuator)-10dB(Mixer)+22dB (IF amplifier) = 24.5dB so your 24dB measurement is in line with what you should see !
For SSB3 the equation looks similar but the filter loss is 3dB and the attenuator is 3dB instead of 7dB so you have 6dB instead of 7.5dB meaning your gain increases to 25.5dB !
Now a few caveats :? SSB2 and SSB3 use a mixer and the conversion loss of a mixer generally depends on the LO power ,? if you have a unit with LO amp than the typical LO power you should feed in the unit is 1dBm which after beein amplified by 10dB and then passed through some cables gives you about 10dBm LO power ,? if you apply a higher LO power the amplifier Pout increases until the amplifier starts compressing, this means that your conversion loss slightly improves at the risk that the power exceeds eventually damage level and the mixer sustains damage , if not then the amplifier will go into compression reducing the gain and Pout of the amplifier so the conversion gain of the mixer will increase as the lo power coming from the buffer amp starts dropping .......? so if your unit has the LO amplifier (option 001 or 001/002) make sure you keep your LO at or below 1dBm ,? if the unit does not have LO buffer amp than your LO should be typically around 7-10dB !
Last but not least keep in mind that the YIG filter has a bandwidth of only 10-30MHz , your 8970B has a fixed IF BW of 4MHz so if your filter does not track correctly you will be tuned on the flanks of the filter and your loss will increase significantly above the 3dB in the center of the passband , the fact that your gain increases when you tune your signal source shows this is what is happening here .
This is why you normally when you put together a system you perform the coarse and fine peaking procedure outlined in the manual and repeat it every now and then
i hope this helps?
|
Re: HP 8970B System Check
Another thing you could do to check the filters is sweep the input signal and look at the filter profile (constant LO) on a spectrum analyzer.
Cheers!
Bruce
Quoting bruce@...:
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Show quoted text
Based on your reported measurements, I'm wondering if the appropriate filter set for the selected measurement is actually happening. Unfortunately, this can only be confirmed by opening and measuring.
Another possible approach would be to measure the relative noise power (no signal in or a known noise source in) would give an approximation of the actual bandwidth provided by the selected filters.
Cheers!
Bruce
Quoting Matt Huszagh <huszaghmatt@...>:
"Lothar baier" <Lothar@...> writes:
It sounds to me like your YIG filter is not peaked, you might need to run the adjustments for the yig driver ! Thanks for the input Lothar.
The only adjustments actually described in the HP 8971C manual are power
supply adjustments. The troubleshooting section for the YIG filter
driver basically has the technician check a number of voltages and
replace components when the voltages are out of spec. Is the power
supply adjustments what you're referring to?
The +20V supply is used to power the YIG driver and is one of the
supplies that can be adjusted. However, the acceptable range isn't that
narrow: +-0.1V.
Thanks
Matt
|
Re: HP 8970B System Check
Based on your reported measurements, I'm wondering if the appropriate filter set for the selected measurement is actually happening. Unfortunately, this can only be confirmed by opening and measuring.
Another possible approach would be to measure the relative noise power (no signal in or a known noise source in) would give an approximation of the actual bandwidth provided by the selected filters.
Cheers!
Bruce
Quoting Matt Huszagh <huszaghmatt@...>:
toggle quoted message
Show quoted text
"Lothar baier" <Lothar@...> writes:
It sounds to me like your YIG filter is not peaked, you might need to run the adjustments for the yig driver ! Thanks for the input Lothar.
The only adjustments actually described in the HP 8971C manual are power
supply adjustments. The troubleshooting section for the YIG filter
driver basically has the technician check a number of voltages and
replace components when the voltages are out of spec. Is the power
supply adjustments what you're referring to?
The +20V supply is used to power the YIG driver and is one of the
supplies that can be adjusted. However, the acceptable range isn't that
narrow: +-0.1V.
Thanks
Matt
|
Re: HP 8970B System Check
"Lothar baier" <Lothar@...> writes: It sounds to me like your YIG filter is not peaked, you might need to run the adjustments for the yig driver ! Thanks for the input Lothar. The only adjustments actually described in the HP 8971C manual are power supply adjustments. The troubleshooting section for the YIG filter driver basically has the technician check a number of voltages and replace components when the voltages are out of spec. Is the power supply adjustments what you're referring to? The +20V supply is used to power the YIG driver and is one of the supplies that can be adjusted. However, the acceptable range isn't that narrow: +-0.1V. Thanks Matt
|
Facebook marketplace worked out well this weekend, and I picked up an
HP8560E, SN 3517A01857. It's in good shape, powers up with no errors
and has a good display. Is there any recommended maintenance/battery
changes I should be aware of?
Thanks
Dave
|
Re: ESA instrument adjustments - reverse engineering
This is a lot of work ! Congrats and thank you !? Ing. Patricio A. GrecoTaller Aeron¨¢utico de Reparaci¨®n 1B-349Organizaci¨®n de Mantenimiento Aeron¨¢utico de la Defensa OMAD-001Gral. Mart¨ªn Rodr¨ªguez 2159San Miguel (1663)Buenos AiresT:?+5411-4455-2557F:?+5411-4032-0072
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Show quoted text
On 5 Jun 2022, at 17:00, Kalle Kempe <kalle.kempe@...> wrote:
?Hello Everyone, While working on my own E4407B I uncovered a few things. My own machine had an untuned YTF in the RYTHM which I have since successfully corrected. I discovered from the N7800 docs that no special equipment is used except an external synthesizer with great enough frequency range and a GPIB interface. I therefore set about looking for hidden commands for the SCPI interface. Here are some that I have found so far, with my own notes on format/function calls. Disclaimer: Using these commands can mess with your calibration data, making your unit worse. Please use with caution. SCPI Command Function call
DIAG:CAL:ADC?\n
DIAG:CAL? nnn,n\n GetStateEEPROM, nnn,n = address
DIAG:CAL nnn,n,xxx.yyy\n SetStateEEPROMData (RAM), nnn,n = address, xxx.yyy = new value
DIAG:CAL:BEG\n SetStateEEPROMBegin
DIAG:CAL:STOR %s\n SetStateEEPROMStore
DIAG:CAL:END\n SetStateEEPROMEnd
DIAG:CAL:SOUR?\n GetStateCalSource
DIAG:CAL:SOUR %s\n SetStateCalSource
SYST:PASS %s\n SetStatePassword
DIAG:CAL:PIECE %s\n SetStateUpdate
DIAG:OPT %s\n SetStateEEPROMOption
DIAG:PARK:LO?\n GetStateParkLO
DIAG:PARK:LO %d\n SetStateParkLO
DIAG:CARD? %s\n GetStateInformation
DIAG:TEMP? %s\n GetStateTemperature
DIAG:LATC:VAL %f\n SetStateRAM
DIAG:LATC:SEL %s\n
DIAG:LATC:VAL?\nGetStateRAM
In addition, I have started mapping out the address space accessible with the DIAG:CAL? nnn,n command. Here a few of the addresses and their corresponding register contents
Addr: Keyword:43,0 TG CAL OFFSET43,1 TG CAL SLOPE111,0 IF CAL LEVEL112,0 RF CAL LEVEL112,0 112,1 50 MHZ CAL ADJUST DAC (EEPROM)?113,0 COARSE SET FREQ REF113,1 FINE SET FREQ REF114,0 LO LEVEL DAC (EEPROM)115,0 COARSE RF GAIN DAC120,0 BITG LO LEVEL DAC (EEPROM)121,0 TG CORNER122,0 TG MOD OFFSET123,0 TG GAIN124,0 TG A OFFSET124,1 TG LB OFFSET124,2 TG A SLOPE125,0 TG X OFFSET125,1 TG X SLOPE126,0 TG F SLOPE131,0 FEXT B1 LO LEVEL DAC131,1 FEXT B2 LO LEVEL DAC131,2 FEXT B3 LO LEVEL DAC131,3 FEXT B4 LO LEVEL DAC131,4 FEXT TG LO LEVEL DAC131,5 FEXT B5 LO LEVEL DAC131,6 FEXT MIX LO LEVEL DAC132,0 YTF TUNE A0132,1 YTF TUNE A1132,2 YTF TUNE A2132,3 YTF TUNE A3132,4 YTF TUNE EXT 0132,5 YTF TUNE EXT 1132,6 YTF TUNE EXT 2132,7 YTF TUNE EXT 3133,0 FEXT YTF DELAY OFFSET 0133,1 FEXT YTF DELAY OFFSET 1133,2 FEXT YTF DELAY OFFSET 2133,3 FEXT YTF DELAY OFFSET 3133,4 FEXT YTF DELAY OFFSET 4133,5 FEXT YTF DELAY OFFSET 5133,6 FEXT YTF DELAY OFFSET 6133,7 FEXT YTF DELAY OFFSET 7133,8 FEXT YTF DELAY OFFSET 8133,9 FEXT YTF DELAY OFFSET 9134,0 B0 REF TEMP PA OFF 0134,1 B0 REF TEMP PA OFF 1134,2 B0 REF TEMP PA OFF 2135,0 B0 REF TEMP PA ON 0135,1 B0 REF TEMP PA ON 1135,2 B0 REF TEMP PA ON 2136,0 B1 REF TEMP 0136,1 B1 REF TEMP 1136,2 B1 REF TEMP 2137,0 B2 REF TEMP 0137,1 B2 REF TEMP 1137,2 B2 REF TEMP 2138,0 B3 REF TEMP 0138,1 B3 REF TEMP 1138,2 B3 REF TEMP 2139,0 B4 REF TEMP 0139,1 B4 REF TEMP 1139,2 B4 REF TEMP 2140,0 LO PRETUNE CONST 0140,1 LO PRETUNE CONST 1142,0 FEXT YTF DELAY SLOPE 0142,1 FEXT YTF DELAY SLOPE 1142,2 FEXT YTF DELAY SLOPE 2142,3 FEXT YTF DELAY SLOPE 3142,4 FEXT YTF DELAY SLOPE 4142,5 FEXT YTF DELAY SLOPE 5142,6 FEXT YTF DELAY SLOPE 6142,7 FEXT YTF DELAY SLOPE 7142,8 FEXT YTF DELAY SLOPE 8142,9 FEXT YTF DELAY SLOPE 9143,0 FEXT BREATHING ROOM 0143,1 FEXT BREATHING ROOM 1143,2 FEXT BREATHING ROOM 2143,3 FEXT BREATHING ROOM 3145,0 FEXT PULSE WIDTH145,1 FEXT SWEEP DWELL145,2 FEXT OVERTUNE FREQ145,3 FEXT OVERTUNE STATE145,4 FEXT MIX PULSE WIDTH145,5 FEXT MIX SWEEP DWELL145,6 FEXT MIX OVERTUNE FREQ145,7 FEXT MIX OVERTUNE STATE145,6 FEXT MIX OVERTUNE FREQ146,0 B5 REF TEMP 0146,1 B5 REF TEMP 1146,2 B5 REF TEMP 2147,0 EXT MIX REF TEMP 0147,1 EXT MIX REF TEMP 1147,2 EXT MIX REF TEMP 2
Perhaps with the community's help we can find out more on these units and work together on keeping them running going forwards. Best regards
|
Re: HP 8662A - alternative attenuator configurations, 8663A Last Rev Mnl
No problem, I would be happy to help get them digitized! I can definitely do 600dpi. If you are already looking to get a nice scanner for doing manuals I would definitely recommend the epson- it has been a game changer for me. As I'm sure we are all aware, keep an eye on "broken" and "for parts" from recyclers/resellers as often times the fix is trivial (though NOT always, HAH).
Richard, if you need more info from me let me know. I am just a random person on the internet so I completely understand if you'd rather go with someone more known. I live in Minnesota.
-Michael
|
Re: HP 8116A woes with E42 error
Hi David,
Congratulations for the repair. I am in San Francisco Bay Area (aka Silicon Valley). If you are close by or have plans to visit beer sounds good.?
Ozan
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On Sat, Jun 4, 2022 at 03:34 PM, Swiss wrote:
Ozan and Raymond,
Q502 was it. Emitter-base junction was wide open.? Replaced it with the most similar PNP I could find in a 2n5771. E42 error is gone, and I have a full sine wave at both full positive and negative offset. The 5771 is not really a small signal transistor, but will see what happens in due time.
Will need to calibrate, but these 8116A are almost a whole day affair to cal. Looks dead on at first glance though. Probably will stay up late this evening and fix her up after I let her run for a couple of hours.
If both of ya are close, I'd take ya out for a beer. If ya don't drink, i'd get ya a coffee.
Hope this post helps others with the same fault I had in the future by reading this thread, and what a good resource this group is.
Thanks for the help,
David
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ESA instrument adjustments - reverse engineering
Hello Everyone, While working on my own E4407B I uncovered a few things. My own machine had an untuned YTF in the RYTHM which I have since successfully corrected. I discovered from the N7800 docs that no special equipment is used except an external synthesizer with great enough frequency range and a GPIB interface. I therefore set about looking for hidden commands for the SCPI interface. Here are some that I have found so far, with my own notes on format/function calls. Disclaimer: Using these commands can mess with your calibration data, making your unit worse. Please use with caution. SCPI Command Function call
DIAG:CAL:ADC?\n
DIAG:CAL? nnn,n\n GetStateEEPROM, nnn,n = address
DIAG:CAL nnn,n,xxx.yyy\n SetStateEEPROMData (RAM), nnn,n = address, xxx.yyy = new value
DIAG:CAL:BEG\n SetStateEEPROMBegin
DIAG:CAL:STOR %s\n SetStateEEPROMStore
DIAG:CAL:END\n SetStateEEPROMEnd
DIAG:CAL:SOUR?\n GetStateCalSource
DIAG:CAL:SOUR %s\n SetStateCalSource
SYST:PASS %s\n SetStatePassword
DIAG:CAL:PIECE %s\n SetStateUpdate
DIAG:OPT %s\n SetStateEEPROMOption
DIAG:PARK:LO?\n GetStateParkLO
DIAG:PARK:LO %d\n SetStateParkLO
DIAG:CARD? %s\n GetStateInformation
DIAG:TEMP? %s\n GetStateTemperature
DIAG:LATC:VAL %f\n SetStateRAM
DIAG:LATC:SEL %s\n
DIAG:LATC:VAL?\nGetStateRAM
In addition, I have started mapping out the address space accessible with the DIAG:CAL? nnn,n command. Here a few of the addresses and their corresponding register contents
Addr: Keyword:43,0 TG CAL OFFSET43,1 TG CAL SLOPE111,0 IF CAL LEVEL112,0 RF CAL LEVEL112,0 112,1 50 MHZ CAL ADJUST DAC (EEPROM)?113,0 COARSE SET FREQ REF113,1 FINE SET FREQ REF114,0 LO LEVEL DAC (EEPROM)115,0 COARSE RF GAIN DAC120,0 BITG LO LEVEL DAC (EEPROM)121,0 TG CORNER122,0 TG MOD OFFSET123,0 TG GAIN124,0 TG A OFFSET124,1 TG LB OFFSET124,2 TG A SLOPE125,0 TG X OFFSET125,1 TG X SLOPE126,0 TG F SLOPE131,0 FEXT B1 LO LEVEL DAC131,1 FEXT B2 LO LEVEL DAC131,2 FEXT B3 LO LEVEL DAC131,3 FEXT B4 LO LEVEL DAC131,4 FEXT TG LO LEVEL DAC131,5 FEXT B5 LO LEVEL DAC131,6 FEXT MIX LO LEVEL DAC132,0 YTF TUNE A0132,1 YTF TUNE A1132,2 YTF TUNE A2132,3 YTF TUNE A3132,4 YTF TUNE EXT 0132,5 YTF TUNE EXT 1132,6 YTF TUNE EXT 2132,7 YTF TUNE EXT 3133,0 FEXT YTF DELAY OFFSET 0133,1 FEXT YTF DELAY OFFSET 1133,2 FEXT YTF DELAY OFFSET 2133,3 FEXT YTF DELAY OFFSET 3133,4 FEXT YTF DELAY OFFSET 4133,5 FEXT YTF DELAY OFFSET 5133,6 FEXT YTF DELAY OFFSET 6133,7 FEXT YTF DELAY OFFSET 7133,8 FEXT YTF DELAY OFFSET 8133,9 FEXT YTF DELAY OFFSET 9134,0 B0 REF TEMP PA OFF 0134,1 B0 REF TEMP PA OFF 1134,2 B0 REF TEMP PA OFF 2135,0 B0 REF TEMP PA ON 0135,1 B0 REF TEMP PA ON 1135,2 B0 REF TEMP PA ON 2136,0 B1 REF TEMP 0136,1 B1 REF TEMP 1136,2 B1 REF TEMP 2137,0 B2 REF TEMP 0137,1 B2 REF TEMP 1137,2 B2 REF TEMP 2138,0 B3 REF TEMP 0138,1 B3 REF TEMP 1138,2 B3 REF TEMP 2139,0 B4 REF TEMP 0139,1 B4 REF TEMP 1139,2 B4 REF TEMP 2140,0 LO PRETUNE CONST 0140,1 LO PRETUNE CONST 1142,0 FEXT YTF DELAY SLOPE 0142,1 FEXT YTF DELAY SLOPE 1142,2 FEXT YTF DELAY SLOPE 2142,3 FEXT YTF DELAY SLOPE 3142,4 FEXT YTF DELAY SLOPE 4142,5 FEXT YTF DELAY SLOPE 5142,6 FEXT YTF DELAY SLOPE 6142,7 FEXT YTF DELAY SLOPE 7142,8 FEXT YTF DELAY SLOPE 8142,9 FEXT YTF DELAY SLOPE 9143,0 FEXT BREATHING ROOM 0143,1 FEXT BREATHING ROOM 1143,2 FEXT BREATHING ROOM 2143,3 FEXT BREATHING ROOM 3145,0 FEXT PULSE WIDTH145,1 FEXT SWEEP DWELL145,2 FEXT OVERTUNE FREQ145,3 FEXT OVERTUNE STATE145,4 FEXT MIX PULSE WIDTH145,5 FEXT MIX SWEEP DWELL145,6 FEXT MIX OVERTUNE FREQ145,7 FEXT MIX OVERTUNE STATE145,6 FEXT MIX OVERTUNE FREQ146,0 B5 REF TEMP 0146,1 B5 REF TEMP 1146,2 B5 REF TEMP 2147,0 EXT MIX REF TEMP 0147,1 EXT MIX REF TEMP 1147,2 EXT MIX REF TEMP 2
Perhaps with the community's help we can find out more on these units and work together on keeping them running going forwards. Best regards
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Re: HP 8970B System Check
It sounds to me like your YIG filter is not peaked, you might need to run the adjustments for the yig driver !?
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On Jun 5, 2022, at 14:44, Matt Huszagh via groups.io <huszaghmatt@...> wrote:
? I've performed some of the microwave troubleshooting described in the HP
8971C service manual. The microwave circuitry in the 8971C test set
consists of a number of paths selected with relays. These paths consist
of a simple pass-through for low frequencies directly handled by the
8970B and filters and a downconversion mixer for higher frequencies (to
translate RF frequencies to an input frequency the 8970B can
handle). I've attached an image from the service manual showing these
paths.
The first part of the troubleshooting section involves injecting an RF
signal, selecting a path, measuring the signal gain, and comparing it
with the gain computed from the individual component gains. I've also
attached an image showing these individual component gains.
The gains I measure differ a fair amount from the predicted gains.
In SSB (single sideband) 1 I'm measuring a gain of approximately 23 dB
instead of the expected 15 dB. Moreover, this gain is pretty flat across
the bandwidth as tested by moving the RF signal in 100 MHz steps.
In SSB 2, I also measure a gain in excess of the predicted value. In
this case, 24 dB instead of 19 dB expected.
In SSB 3, I measure a gain of about 16 dB instead of the 20.5 dB
expected. If I move the RF signal by 10-20 MHz (without adjusting the LO
frequency) the gain moves up more toward the expected value.
Any thoughts on what might be going wrong here? SSBs 1 and 2 suggest to
me that maybe the attenuator (AT3) is passing the signal through
un-attenuated. However, the test for SSB 3 indicates that if this is
true, then the YIG filter + attenuator combo is attenuating the signal
by a margin even more than that predicted by the third test on it's own,
which is concerning. Unfortunately, I've only been able to test SSB 3
operation at the low end of its range (2.5 GHz). I'm using my 8340 as
the LO and the only other RF signal generator I have is an 8663A, which
tops out at 2560 MHz. I've got an 8341 too, but it needs repairs.
An obvious solution to these problems would be to open up the instrument
and test components individually. Unfortunately, I can't do that yet as
I bought this unit in a supposedly functional state and may lose my
right to return it if I open it up.
All thoughts appreciated.
Thanks
Matt
 
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Re: HP 8970B System Check
I've performed some of the microwave troubleshooting described in the HP
8971C service manual. The microwave circuitry in the 8971C test set
consists of a number of paths selected with relays. These paths consist
of a simple pass-through for low frequencies directly handled by the
8970B and filters and a downconversion mixer for higher frequencies (to
translate RF frequencies to an input frequency the 8970B can
handle). I've attached an image from the service manual showing these
paths.
The first part of the troubleshooting section involves injecting an RF
signal, selecting a path, measuring the signal gain, and comparing it
with the gain computed from the individual component gains. I've also
attached an image showing these individual component gains.
The gains I measure differ a fair amount from the predicted gains.
In SSB (single sideband) 1 I'm measuring a gain of approximately 23 dB
instead of the expected 15 dB. Moreover, this gain is pretty flat across
the bandwidth as tested by moving the RF signal in 100 MHz steps.
In SSB 2, I also measure a gain in excess of the predicted value. In
this case, 24 dB instead of 19 dB expected.
In SSB 3, I measure a gain of about 16 dB instead of the 20.5 dB
expected. If I move the RF signal by 10-20 MHz (without adjusting the LO
frequency) the gain moves up more toward the expected value.
Any thoughts on what might be going wrong here? SSBs 1 and 2 suggest to
me that maybe the attenuator (AT3) is passing the signal through
un-attenuated. However, the test for SSB 3 indicates that if this is
true, then the YIG filter + attenuator combo is attenuating the signal
by a margin even more than that predicted by the third test on it's own,
which is concerning. Unfortunately, I've only been able to test SSB 3
operation at the low end of its range (2.5 GHz). I'm using my 8340 as
the LO and the only other RF signal generator I have is an 8663A, which
tops out at 2560 MHz. I've got an 8341 too, but it needs repairs.
An obvious solution to these problems would be to open up the instrument
and test components individually. Unfortunately, I can't do that yet as
I bought this unit in a supposedly functional state and may lose my
right to return it if I open it up.
All thoughts appreciated.
Thanks
Matt
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Patricio A. Greco
