Re: low amplitude readings below 10MHz on a 8591E
I must be missing something... Aren't you already going to: "poke a soldering iron around in the A16 pcb..." when you replace the battery? Hand copying data onto a list, and then back from the list into the instrument sounds like a great place to make a few mistakes... Or, so it seems to me, as one who can effortlessly type at a rate of over 40 errors per minute. -Chuck Harris On Wed, 22 Mar 2023 17:45:42 -0000 "Mike Lockley via groups.io" <mikelockley@...> wrote: As it is so simple to restore the data after the battery is removed
,I personally would not like to poke a soldering iron around in the
A16 pcb. That¡¯s my opinion anyway Regards
Mike g4wam
|
Re: HP 8656B display issue
Andrew, Do you have the service manual? The first thing that comes to mind is if you get the correct output even when the display is wrong, it may be the display shift registers. Service sheet 22 in the manual covers the display. The display decoders seem fine since no digit segments are missing.?
On Sat, Mar 18, 2023, 8:50 AM Andrew Curlik < kb2lmn@...> wrote: Video of what¡¯s happening??
?
|
Re: low amplitude readings below 10MHz on a 8591E
As it is so simple to restore the data after the battery is removed ,I personally would not like to poke a soldering iron around in the A16 pcb.
That¡¯s my opinion anyway
Regards
Mike g4wam
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Chuck Harris Sent: 22 March 2023 17:31 To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E Given that it is so trivial to connect a backup supply in parallel before you remove the old, but still holding data cell, why wouldn't you? Usually, non chargeable backup batteries are connected to the memory's logic supply through a diode, and the 5V (or whatever) logic supply is also connected to the memory's logic supply through a diode, just connect the backup battery to the junction of those two diode's cathodes, before you remove the original and solder in the new. Be warned that most soldering irons have tips that are grounded to the power line bonding circuit. -Chuck Harris On Wed, 22 Mar 2023 14:13:27 -0000 "Mike Lockley via groups.io" <mikelockley@...> wrote: Gr Kees,
There 2 battery types ¨Ccylindrical and disc shaped.
The older is cylindrical ¨Cit will probably be on its last gasps so
check the voltage before you remove it.
It is not backed up by a charger circuit., therefore when you change
it you will lose all the factory set up data so make sure you read
through the restore pages procedure and have all the data to hand,
The options if you have any will recover themselves except for the
gate option ¨Cbut I have the restore procedure for that.
Regards
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 21 March 2023 20:09 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
HI Mike,
battery date almost not readable but it looks like the last part of
the year is 32 so should be 83, 93
so I'll replace it after viewing some video's.
After replacement I'll see what the state is like.
The moisture in the shed is never above 60% so no moisture issues.
Tx for the help
Gr. Kees
Op di 21 mrt 2023 om 20:00 schreef Mike Lockley via groups.io
<mikelockley@...>:
Gr Kees,
My observation from what you are saying is that the unit is getting
too cold ¨Cthese units should be at room temp all the time.
The YTO LO does not like getting towards condensation levels ¨Cthey
have no heater built in to the YIG assy.
Also, what is the state of the internal 3.7v battery?
There should be a date on the back of the SA with the replacement
date .
If the battery is failing or failed you will get CAL fail problems
There is a lot of info on YouTube about battery replacement.
Regards
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 21 March 2023 18:24 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
hi Mike,
CAL FREQUENCY passes yes
CAL AMPTD ¨Cpasses with CAL link in place?
After switching it on tonight ( sched was about 13 C) it failed, but
with the marconi 300Mhz at -20dBm it did,
after that with the CAL link it passed the amptd CAL
CONFIDENCE TEST ? STEP GAIN ATTEN FAIL -6000 SQR 110
Will do it again after a 1 hr warmup
Gr. Kees
Op ma 20 mrt 2023 om 21:46 schreef Mike Lockley via groups.io
<mikelockley@...>:
That suggests a very strong LO signal ¨Ca good thing so probably not
a YTO fault,
Just to clarify..
CAL FREQUENCY passes
CAL AMPTD ¨Cpasses with CAL link in place?
CONFIDENCE TEST ?
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 20 March 2023 19:50 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
Hi Mike its
10dBm above the ref lvl. with 10 db ATTEN
Gr. Kees
Op ma 20 mrt 2023 om 20:43 schreef Mike Lockley via groups.io
<mikelockley@...>:
Gr Kees,
Did you take a look at the 0hz feedthrough amplitude ¨C(left side of
display)
What value is it?
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 20 March 2023 19:28 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
Hi Mike,
I've backup the constants ( paper) and used my marconi frequency
generator to have the amptd NOT fail.
After that the cal signal of the 8591E was used to do an amptd again
and this time it succeeded.
Still the lower end is terrible ( low amplitude ). I've done the
service diag and
1. the MAIN Coil driver is much steeper and starts higher at the
-20dbm horizontal line
The rest has the same picture as shown in the 8590-90316 manual.
So according to the manual it's in the A7 board. does somebody have a
spare will to sell
or is too premature.
Gr Kees
Op za 18 mrt 2023 om 20:20 schreef Mike Lockley via groups.io
<mikelockley@...>:
Hi
in your case from 238-247
if you haven¡¯t done it already ..201 onwards backing up correction
constants
One thing to check is the level of your LO feedthrough amplitude
..the signal at 0hz on the left hand edge of the display
Do frequency 0hz span 1mhz¡ and see what the level of the LO is
--good ones are around -10db or better.
By the way you¡¯re 8591 is a bit different on the front end than the
8590e series , yours is more prone to mixer failure but can be fixed .
Lots of info on you tube
Regards
Mike g4wam
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 18 March 2023 17:47 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
got it and will start reading.
Any recommendations about what paragraph?
Gr Kees
Op za 18 mrt 2023 om 18:19 schreef Mike Lockley via groups.io
<mikelockley@...>:
You need 08590-90316 from 2001
8590 series Service Guide
Are large tome but worth downloading or buying
¸é±ð²µ²¹°ù»å¡¯²õ
Mike g4wam
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 18 March 2023 14:41 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
Hi,
Are we talking about the user manual 08590-90301, because there is
not much cal data in it
other than the normal stuff. I also have the installation,
verification & Operation manual.
Or are there other manual I need?
Gr. Kees
|
Re: low amplitude readings below 10MHz on a 8591E
Given that it is so trivial to connect a backup supply in parallel before you remove the old, but still holding data cell, why wouldn't you? Usually, non chargeable backup batteries are connected to the memory's logic supply through a diode, and the 5V (or whatever) logic supply is also connected to the memory's logic supply through a diode, just connect the backup battery to the junction of those two diode's cathodes, before you remove the original and solder in the new. Be warned that most soldering irons have tips that are grounded to the power line bonding circuit. -Chuck Harris On Wed, 22 Mar 2023 14:13:27 -0000 "Mike Lockley via groups.io" <mikelockley@...> wrote: Gr Kees,
There 2 battery types ¨Ccylindrical and disc shaped.
The older is cylindrical ¨Cit will probably be on its last gasps so
check the voltage before you remove it.
It is not backed up by a charger circuit., therefore when you change
it you will lose all the factory set up data so make sure you read
through the restore pages procedure and have all the data to hand,
The options if you have any will recover themselves except for the
gate option ¨Cbut I have the restore procedure for that.
Regards
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 21 March 2023 20:09 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
HI Mike,
battery date almost not readable but it looks like the last part of
the year is 32 so should be 83, 93
so I'll replace it after viewing some video's.
After replacement I'll see what the state is like.
The moisture in the shed is never above 60% so no moisture issues.
Tx for the help
Gr. Kees
Op di 21 mrt 2023 om 20:00 schreef Mike Lockley via groups.io
<mikelockley@...>:
Gr Kees,
My observation from what you are saying is that the unit is getting
too cold ¨Cthese units should be at room temp all the time.
The YTO LO does not like getting towards condensation levels ¨Cthey
have no heater built in to the YIG assy.
Also, what is the state of the internal 3.7v battery?
There should be a date on the back of the SA with the replacement
date .
If the battery is failing or failed you will get CAL fail problems
There is a lot of info on YouTube about battery replacement.
Regards
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 21 March 2023 18:24 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
hi Mike,
CAL FREQUENCY passes yes
CAL AMPTD ¨Cpasses with CAL link in place?
After switching it on tonight ( sched was about 13 C) it failed, but
with the marconi 300Mhz at -20dBm it did,
after that with the CAL link it passed the amptd CAL
CONFIDENCE TEST ? STEP GAIN ATTEN FAIL -6000 SQR 110
Will do it again after a 1 hr warmup
Gr. Kees
Op ma 20 mrt 2023 om 21:46 schreef Mike Lockley via groups.io
<mikelockley@...>:
That suggests a very strong LO signal ¨Ca good thing so probably not
a YTO fault,
Just to clarify..
CAL FREQUENCY passes
CAL AMPTD ¨Cpasses with CAL link in place?
CONFIDENCE TEST ?
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 20 March 2023 19:50 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
Hi Mike its
10dBm above the ref lvl. with 10 db ATTEN
Gr. Kees
Op ma 20 mrt 2023 om 20:43 schreef Mike Lockley via groups.io
<mikelockley@...>:
Gr Kees,
Did you take a look at the 0hz feedthrough amplitude ¨C(left side of
display)
What value is it?
Mike
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 20 March 2023 19:28 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
Hi Mike,
I've backup the constants ( paper) and used my marconi frequency
generator to have the amptd NOT fail.
After that the cal signal of the 8591E was used to do an amptd again
and this time it succeeded.
Still the lower end is terrible ( low amplitude ). I've done the
service diag and
1. the MAIN Coil driver is much steeper and starts higher at the
-20dbm horizontal line
The rest has the same picture as shown in the 8590-90316 manual.
So according to the manual it's in the A7 board. does somebody have a
spare will to sell
or is too premature.
Gr Kees
Op za 18 mrt 2023 om 20:20 schreef Mike Lockley via groups.io
<mikelockley@...>:
Hi
in your case from 238-247
if you haven¡¯t done it already ..201 onwards backing up correction
constants
One thing to check is the level of your LO feedthrough amplitude
..the signal at 0hz on the left hand edge of the display
Do frequency 0hz span 1mhz¡ and see what the level of the LO is
--good ones are around -10db or better.
By the way you¡¯re 8591 is a bit different on the front end than the
8590e series , yours is more prone to mixer failure but can be fixed .
Lots of info on you tube
Regards
Mike g4wam
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 18 March 2023 17:47 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
got it and will start reading.
Any recommendations about what paragraph?
Gr Kees
Op za 18 mrt 2023 om 18:19 schreef Mike Lockley via groups.io
<mikelockley@...>:
You need 08590-90316 from 2001
8590 series Service Guide
Are large tome but worth downloading or buying
¸é±ð²µ²¹°ù»å¡¯²õ
Mike g4wam
From: [email protected]
[mailto:[email protected]] On Behalf Of
KeesHofwegen Sent: 18 March 2023 14:41 To:
[email protected] Subject: Re:
[HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on
a 8591E
Hi,
Are we talking about the user manual 08590-90301, because there is
not much cal data in it
other than the normal stuff. I also have the installation,
verification & Operation manual.
Or are there other manual I need?
Gr. Kees
|
Dear All
Recently I have got 2 HP 8350B sweep oscillators . And one can work well , another appears " E001 " error . ?These 2 RF plug-ins can all work well when insert to the good 8350B .
To repair?the bad 8350B . I have ?checked all the power on A7 board and on J3 connector , all the values look good . And then I check the J2 connector, all the power values look good and all the signals have been tied to the correct pins in the other board like A5 board , A7 board . These no short or open appear ?.
So I have no good method to check the error . Does anyone can give me some comments for this ??
|
Re: low amplitude readings below 10MHz on a 8591E
Gr Kees, There 2 battery types ¨Ccylindrical and disc shaped. The older is cylindrical ¨Cit will probably be on its last gasps so check the voltage before you remove it. It is not backed up by a charger circuit., therefore when you change it you will lose all the factory set up data so make sure you read through the restore pages procedure and have all the data to hand, The options if you have any will recover themselves? except for the gate option ¨Cbut I have the restore procedure for that. ? ? Regards Mike ? ? ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 21 March 2023 20:09
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? HI Mike, battery date almost not readable but it looks like the last part of the year is 32 so should?be 83, 93 so I'll replace it after viewing some video's. After replacement I'll see what the state is like. The moisture in the shed is never above 60% so no moisture issues. ? Gr Kees, ? My ?observation from what you are saying is that the unit is getting too cold ¨Cthese units should be at room temp all the time. The YTO LO does not like getting towards condensation levels ¨Cthey have no heater built in to the YIG assy. Also, what is the state of the internal 3.7v battery? There should be a date on the back of the SA with the replacement date . If the battery is failing or failed? you will get CAL fail problems There is a lot of info on YouTube about battery replacement. ? Regards Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 21 March 2023 18:24
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? hi Mike, CAL FREQUENCY passes yes CAL AMPTD ¨Cpasses with CAL link in place? After switching it on tonight? ( sched was about 13 C) it failed, but with the marconi 300Mhz at -20dBm it did, after that with? the CAL link it passed?the amptd?CAL ? CONFIDENCE TEST? ? STEP GAIN ATTEN FAIL -6000? SQR 110 ? Will do it again after a 1 hr warmup ? Gr. Kees ? ? That suggests a very strong LO? signal ¨Ca good thing so probably not a YTO fault, Just to clarify.. ? CAL FREQUENCY passes CAL AMPTD ¨Cpasses with CAL link in place? CONFIDENCE TEST? ? ? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:50
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike its? 10dBm above the ref lvl. with 10 db ATTEN ? Gr Kees, Did you take a look at the 0hz feedthrough amplitude ¨C(left side of display) What value ?is it? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:28
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike, I've backup the constants ( paper) and used my marconi frequency?generator?to have the amptd NOT fail. After that the cal signal of the 8591E was used to do an amptd again and this time it succeeded. Still the lower end is terrible ( low amplitude ). I've done the service diag and? 1. the MAIN Coil driver?is much steeper and starts higher at the -20dbm horizontal line? The rest has the same picture as shown in the?8590-90316 manual. So according to the manual it's in the A7 board. does somebody have a spare will to sell ? Hi ?in your case ?from 238-247 if you haven¡¯t done it already? ..201 onwards? ?backing up correction constants ? One thing to check is the level of your LO feedthrough amplitude ?..the signal at 0hz on the left hand edge of the display Do frequency 0hz? span 1mhz¡ and see what the level of the LO is? --good ones are around -10db or better. ? By the way you¡¯re 8591? is a bit different on the front end than the 8590e series , yours is more prone to mixer failure but can be fixed . Lots of info on you tube ? Regards Mike g4wam ? ? ? ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 17:47
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ?
got it and will start reading.?
Any recommendations about what paragraph? ? You need 08590-90316? from? 2001 8590 series Service Guide ? Are large tome but worth downloading or buying ¸é±ð²µ²¹°ù»å¡¯²õ Mike g4wam ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 14:41
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi, Are we talking about the user manual 08590-90301, because there is not much cal data in it other than the normal stuff. I also have the installation, verification & Operation manual. Or are there other manual I need?
|
Re: low amplitude readings below 10MHz on a 8591E
HI Mike, battery date almost not readable but it looks like the last part of the year is 32 so should?be 83, 93 so I'll replace it after viewing some video's. After replacement I'll see what the state is like. The moisture in the shed is never above 60% so no moisture issues.
Tx for the help? Gr. Kees
Gr Kees, ? My ?observation from what you are saying is that the unit is getting too cold ¨Cthese units should be at room temp all the time. The YTO LO does not like getting towards condensation levels ¨Cthey have no heater built in to the YIG assy. Also, what is the state of the internal 3.7v battery? There should be a date on the back of the SA with the replacement date . If the battery is failing or failed? you will get CAL fail problems There is a lot of info on YouTube about battery replacement. ? Regards Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 21 March 2023 18:24
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? hi Mike, CAL FREQUENCY passes yes CAL AMPTD ¨Cpasses with CAL link in place? After switching it on tonight? ( sched was about 13 C) it failed, but with the marconi 300Mhz at -20dBm it did, after that with? the CAL link it passed?the amptd?CAL ? CONFIDENCE TEST? ? STEP GAIN ATTEN FAIL -6000? SQR 110 ? Will do it again after a 1 hr warmup ? Gr. Kees ? ? That suggests a very strong LO? signal ¨Ca good thing so probably not a YTO fault, Just to clarify.. ? CAL FREQUENCY passes CAL AMPTD ¨Cpasses with CAL link in place? CONFIDENCE TEST? ? ? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:50
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike its? 10dBm above the ref lvl. with 10 db ATTEN ? Gr Kees, Did you take a look at the 0hz feedthrough amplitude ¨C(left side of display) What value ?is it? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:28
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike, I've backup the constants ( paper) and used my marconi frequency?generator?to have the amptd NOT fail. After that the cal signal of the 8591E was used to do an amptd again and this time it succeeded. Still the lower end is terrible ( low amplitude ). I've done the service diag and? 1. the MAIN Coil driver?is much steeper and starts higher at the -20dbm horizontal line? The rest has the same picture as shown in the?8590-90316 manual. So according to the manual it's in the A7 board. does somebody have a spare will to sell ? Hi ?in your case ?from 238-247 if you haven¡¯t done it already? ..201 onwards? ?backing up correction constants ? One thing to check is the level of your LO feedthrough amplitude ?..the signal at 0hz on the left hand edge of the display Do frequency 0hz? span 1mhz¡ and see what the level of the LO is? --good ones are around -10db or better. ? By the way you¡¯re 8591? is a bit different on the front end than the 8590e series , yours is more prone to mixer failure but can be fixed . Lots of info on you tube ? Regards Mike g4wam ? ? ? ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 17:47
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ?
got it and will start reading.?
Any recommendations about what paragraph? ? You need 08590-90316? from? 2001 8590 series Service Guide ? Are large tome but worth downloading or buying ¸é±ð²µ²¹°ù»å¡¯²õ Mike g4wam ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 14:41
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi, Are we talking about the user manual 08590-90301, because there is not much cal data in it other than the normal stuff. I also have the installation, verification & Operation manual. Or are there other manual I need?
|
Re: low amplitude readings below 10MHz on a 8591E
Gr Kees, ? My ?observation from what you are saying is that the unit is getting too cold ¨Cthese units should be at room temp all the time. The YTO LO does not like getting towards condensation levels ¨Cthey have no heater built in to the YIG assy. Also, what is the state of the internal 3.7v battery? There should be a date on the back of the SA with the replacement date . If the battery is failing or failed? you will get CAL fail problems There is a lot of info on YouTube about battery replacement. ? Regards Mike ? ? ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 21 March 2023 18:24
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? hi Mike, CAL FREQUENCY passes yes CAL AMPTD ¨Cpasses with CAL link in place? After switching it on tonight? ( sched was about 13 C) it failed, but with the marconi 300Mhz at -20dBm it did, after that with? the CAL link it passed?the amptd?CAL ? CONFIDENCE TEST? ? STEP GAIN ATTEN FAIL -6000? SQR 110 ? Will do it again after a 1 hr warmup ? Gr. Kees ? ? That suggests a very strong LO? signal ¨Ca good thing so probably not a YTO fault, Just to clarify.. ? CAL FREQUENCY passes CAL AMPTD ¨Cpasses with CAL link in place? CONFIDENCE TEST? ? ? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:50
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike its? 10dBm above the ref lvl. with 10 db ATTEN ? Gr Kees, Did you take a look at the 0hz feedthrough amplitude ¨C(left side of display) What value ?is it? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:28
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike, I've backup the constants ( paper) and used my marconi frequency?generator?to have the amptd NOT fail. After that the cal signal of the 8591E was used to do an amptd again and this time it succeeded. Still the lower end is terrible ( low amplitude ). I've done the service diag and? 1. the MAIN Coil driver?is much steeper and starts higher at the -20dbm horizontal line? The rest has the same picture as shown in the?8590-90316 manual. So according to the manual it's in the A7 board. does somebody have a spare will to sell ? Hi ?in your case ?from 238-247 if you haven¡¯t done it already? ..201 onwards? ?backing up correction constants ? One thing to check is the level of your LO feedthrough amplitude ?..the signal at 0hz on the left hand edge of the display Do frequency 0hz? span 1mhz¡ and see what the level of the LO is? --good ones are around -10db or better. ? By the way you¡¯re 8591? is a bit different on the front end than the 8590e series , yours is more prone to mixer failure but can be fixed . Lots of info on you tube ? Regards Mike g4wam ? ? ? ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 17:47
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ?
got it and will start reading.?
Any recommendations about what paragraph? ? You need 08590-90316? from? 2001 8590 series Service Guide ? Are large tome but worth downloading or buying ¸é±ð²µ²¹°ù»å¡¯²õ Mike g4wam ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 14:41
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi, Are we talking about the user manual 08590-90301, because there is not much cal data in it other than the normal stuff. I also have the installation, verification & Operation manual. Or are there other manual I need?
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Re: low amplitude readings below 10MHz on a 8591E
hi Mike, CAL FREQUENCY passes yes CAL AMPTD ¨Cpasses with CAL link in place? After switching it on tonight? ( sched was about 13 C) it failed, but with the marconi 300Mhz at -20dBm it did, after that with? the CAL link it passed?the amptd?CAL ? CONFIDENCE TEST? ? STEP GAIN ATTEN FAIL -6000? SQR 110
Will do it again after a 1 hr warmup
Gr. Kees
That suggests a very strong LO? signal ¨Ca good thing so probably not a YTO fault, Just to clarify.. ? CAL FREQUENCY passes CAL AMPTD ¨Cpasses with CAL link in place? CONFIDENCE TEST? ? ? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:50
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike its? 10dBm above the ref lvl. with 10 db ATTEN ? Gr Kees, Did you take a look at the 0hz feedthrough amplitude ¨C(left side of display) What value ?is it? Mike ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 20 March 2023 19:28
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi Mike, I've backup the constants ( paper) and used my marconi frequency?generator?to have the amptd NOT fail. After that the cal signal of the 8591E was used to do an amptd again and this time it succeeded. Still the lower end is terrible ( low amplitude ). I've done the service diag and? 1. the MAIN Coil driver?is much steeper and starts higher at the -20dbm horizontal line? The rest has the same picture as shown in the?8590-90316 manual. So according to the manual it's in the A7 board. does somebody have a spare will to sell ? Hi ?in your case ?from 238-247 if you haven¡¯t done it already? ..201 onwards? ?backing up correction constants ? One thing to check is the level of your LO feedthrough amplitude ?..the signal at 0hz on the left hand edge of the display Do frequency 0hz? span 1mhz¡ and see what the level of the LO is? --good ones are around -10db or better. ? By the way you¡¯re 8591? is a bit different on the front end than the 8590e series , yours is more prone to mixer failure but can be fixed . Lots of info on you tube ? Regards Mike g4wam ? ? ? ? ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 17:47
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ?
got it and will start reading.?
Any recommendations about what paragraph? ? You need 08590-90316? from? 2001 8590 series Service Guide ? Are large tome but worth downloading or buying ¸é±ð²µ²¹°ù»å¡¯²õ Mike g4wam ? ? From: [email protected] [mailto:[email protected]] On Behalf Of KeesHofwegen
Sent: 18 March 2023 14:41
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] low amplitude readings below 10MHz on a 8591E ? Hi, Are we talking about the user manual 08590-90301, because there is not much cal data in it other than the normal stuff. I also have the installation, verification & Operation manual. Or are there other manual I need?
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Re: HP 312A wave analyser
Good job, Brad.
?
Kr-85 depletion makes the lamp slow to ignite when it¡¯s in the dark, but AFAIK it doesn¡¯t increase the strike voltage.
OTOH, strike voltage does increase as the lamp is used, due to (I think) electrode material adsorbing or contaminating the gas.
Both processes are in play here.
Neon lamps manufactured recently are made without dark-effect-reducing radioactives.
I¡¯d try one anyway since you can get one quicker than you can engineer a LED retrofit.
?
Dave Wise
?
Sent from for Windows
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From: David Holland
Sent: Tuesday, March 21, 2023 5:39 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 312A wave analyser
?
10 years (half life of the Krypton 85 they sometimes stick in neon bulbs, depending on the bulb specification.)
?
I have finally found the problem with the display on my 312A, on the MHZ range nixie, the 2nd from the first LHS, the neon that drives the photo conductor is flickering.
How many hours, or years, of operation does it take before the neon strike voltage point begins to degrade? I may have to start looking at LED substitutes, which I remember being discussed in a previous thread, and clean the range selector switch with de-oxit
? ? ? ? ? ? ? ? ? ? ? ? ? ? Regards Brad?
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Re: Shorted large filter cap - don't they normally go open?
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Re: Shorted large filter cap - don't they normally go open?
A couple of things: The dark goo around the screws is usually simply tar. Older caps, particularly the FP style used tar as a sealant, and to keep the guts from banging around in the can. Also, the electrolyte is very, very, very low resistance stuff. If it leaks and bridges between the electrodes, it will present a dead short at voltage. The more usual case where this will be seen is when a radially leaded capacitor is mounted tight to a PCB. If a leak happens, the electrolyte will pool between the leads, and on traces (if there are any on the component side), and burning can commence. -Chuck Harris On Tue, 21 Mar 2023 13:48:37 +0100 "Martin via groups.io" <musaeum@...> wrote: Hi,
thanks for all these stories.
Although the PSU was running for 20 minutes or so, I did not observe
any signs of heat or smell. The only thing was the dark goo around
the screws.
Could it have vented during this period? There is a little white
deposit on the blank soldered parts around, but not on the wires or
elsewhere. Power consumption of the PSU wasn't higher than expected,
and the 5V rail must have been OK otherwise the analyser would have
stalled.
When the cap shorted the pre-regulator shut down and periodically
tried to start up. No fuse was blown. Not a bad design from that
point of view.
I'll try to reform the cap with Dave's receipt, although it shouldn't
work...
cheers
Martin
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Re: Shorted large filter cap - don't they normally go open?
Hi,
thanks for all these stories.
Although the PSU was running for 20 minutes or so, I did not observe any signs of heat or smell. The only thing was the dark goo around the screws.
Could it have vented during this period? There is a little white deposit on the blank soldered parts around, but not on the wires or elsewhere. Power consumption of the PSU wasn't higher than expected, and the 5V rail must have been OK otherwise the analyser would have stalled.
When the cap shorted the pre-regulator shut down and periodically tried to start up. No fuse was blown. Not a bad design from that point of view.
I'll try to reform the cap with Dave's receipt, although it shouldn't work...
cheers
Martin
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Re: HP 312A wave analyser
10 years (half life of the Krypton 85 they sometimes stick in neon bulbs, depending on the bulb specification.)
I have finally found the problem with the display on my 312A, on the MHZ range nixie, the 2nd from the first LHS, the neon that drives the photo conductor is flickering. How many hours, or years, of operation does it take before the neon strike voltage point begins to degrade? I may have to start looking at LED substitutes, which I remember being discussed in a previous thread, and clean the range selector switch with de-oxit ? ? ? ? ? ? ? ? ? ? ? ? ? ? Regards Brad?
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Re: HP 312A wave analyser
I have finally found the problem with the display on my 312A, on the MHZ range nixie, the 2nd from the first LHS, the neon that drives the photo conductor is flickering. How many hours, or years, of operation does it take before the neon strike voltage point begins to degrade? I may have to start looking at LED substitutes, which I remember being discussed in a previous thread, and clean the range selector switch with de-oxit ? ? ? ? ? ? ? ? ? ? ? ? ? ? Regards Brad?
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Re: Shorted large filter cap - don't they normally go open?
Yep, I too have found low voltage "large value" electrolytic cap's self-depolarise if left unused for some years (10+!)
If you suddenly hit them with the full operating voltage (and ripple current) the resulting heat generated internally can result in the infamous "smelly snow storm" as the insides are ejected via the vent, or explosively by firing the entire end cap off the can!
Or, the internal distort and go short cct.? Also sometimes creating a lot of heat and pressure, but usually something else up-stream opens up, hopefully a fuse of circuit breaker first.
I have though had fair success in recovering them, but you need to check them "BEFORE" applying main power.
The last I recovered (some years ago, based on previous experience with HV electrolytics) were a bank of three 31000uF/40V caps, from a very old computer PSU.
When checked with a meter, they were virtually short cct.? (All three, individually!)
As I wished to use them as a bank of three again, I set up a lab PSU (with diode & fuse in series on the output) for some 41V, and less than 25mA current limit.
It took several months (4+!) before the current limit light went out, but they came back to life (as indicated by slowly rising terminal voltage) and are happy again with low leakage running at some 28V average (37V peak) running stone cold.? Also their "capacity" is not far above 100,000uF total again.?? Didn't measure ESR, but the way things were working, and cool with it, I don't think there is an issue there.? (The application was an 18V raw DC PSU, upstream of several DC/DC buck converters.)
The disadvantage with this, is the time it takes.? The slower the better.? (If the terminal voltage does not start to rise after some days, or stays at a low level without moving (or even fall's back!) Then it's probably not going to recover.)
Small wire ended electrolytic cap's also suffer, but the useful recovery rate is abysmal.? There again, the replacements are much more economic than trying to source those "bin sized" monsters.
This is based on my own experience over the years.
Remember too, that a large value cap with even a moderate voltage, stores a considerable amount of energy, that at best can cause damage to other things,? At worst, well...? Take care.
Dave G8KBV
--
Created on and sent from a Unix like PC running and using free and open source software:
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Re: Shorted large filter cap - don't they normally go open?
I¡¯ve had a big Sprague electrolytic in a lab supply, 60s vintage, fail in a Zener-like mode. Up to a couple volts it was fine, then its differential resistance dropped pretty much to zero per curve tracer.
I also was not quite expecting that.
Cheers, Kuba
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21 mars 2023 kl. 4:52 fm skrev Martin via groups.io <musaeum@...>:
?Hi all, a W&G switching power supply in my SNA1 spectrum analyzer had a large 15mF filter cap with a total short. The screws showed some brown-black goo, otherwise no sign of failure like overheating. Another capacitor of the same type is perfectly in spec. Once the capacitor replaced the supply and the rest seems to work fine. Up to now I thought these caps gradually loose capacity and go open. Here is the first time I've seen one shorted. The supply worked for 20 minutes or so before it failed. Before that it was unused for years, and when switched on it was stressed by a shorted through capacitor in the -12V supply. The 15mF capacitor belongs to the 5V supply, probably unrelated. Any opinion on this? cheers Martin
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Re: Shorted large filter cap - don't they normally go open?
On Tue, Mar 21, 2023 at 11:24?AM Martin Rickes < MRickes@...> wrote: Hi Martin,
I had this several times already. Last time in the PSU of an old HP DSO.? That one failed quite spectacularly?(masclet¨¢!!!) before the circuit-braker?kicked in. It's rare, yes, but not impossible :-)
in my experience not so rare actually. I had at least 4 electrolytics failing short on HP and Schlumberger instruments? (470 to 1000 uF filter capacitors on DC supply rails) and in one occasion, 4 big 10000uF 63V capacitors going short circuit on an audio amplifier's DC power rails. These could be temporarily fixed by slowly increasing the DC voltage across the capacitors. But the capacitor would fail again shorted after a few weeks if left unpowered. ?These would kill 10 amps fuses in a quite "loud" way until all of them were replaced.
HTH Frank IZ8DWF
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Re: Shorted large filter cap - don't they normally go open?
Hi Martin,
I had this several times already. Last time in the PSU of an old HP DSO.? That one failed quite spectacularly?(masclet¨¢!!!) before the circuit-braker?kicked in. It's rare, yes, but not impossible :-)
Cheers, Martin
Hi all,
a W&G switching power supply in my SNA1 spectrum analyzer had a large 15mF filter cap with a total short. The screws showed some brown-black goo, otherwise no sign of failure like overheating. Another capacitor of the same type is perfectly in spec. Once the capacitor replaced the supply and the rest seems to work fine.
Up to now I thought these caps gradually loose capacity and go open. Here is the first time I've seen one shorted. The supply worked for 20 minutes or so before it failed. Before that it was unused for years, and when switched on it was stressed by a shorted through capacitor in the -12V supply. The 15mF capacitor belongs to the 5V supply, probably unrelated.
Any opinion on this?
cheers
Martin
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Re: Fixed my HP 5345A today!!
Can we please start a new topic, rather than continuing to use the same old, now misleading Subject line? None of the last 10 respondents said anything about the HP 5345A. 73 de Brian, VK2GCE
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Martin
Martin Rickes
Brian