开云体育

  1. HP-Agilent-Keysight-Equipment
  2. Messages
Expanded Topics Messages
Date
Re: Understanding the 8753ES frequency loop

 

开云体育

This is beginning to line up.?

3.5 volts at 300 kHz,
3.5 volts across a 40 ohm resistor = 87.5 mA,
87.5 mA divided by 23 mA/GHz = 3.804 GHz,
Right in the correct 1-6 MHz high stated range.?




Peter

On Mar 21, 2019, at 4:17 PM, pianovt via Groups.Io <pianovt@...> wrote:

It's a straight line, so pick any frequency you want. There is a non-linearity starting above 5.5 GHz or so. But, you are having problems at the low end, below 1 GHz rf out. That means the YTO is tuned to ~4.8 GHz when the rf output is 1 GHz.. Let's say you pick 4 GHz as a test point. The current should be 4 x 23 = 92 mA. If the actual coil sensitivity is at the upper limit (24 mA/GHz), then 96 mA.

Vladan

Re: I'm officially lost now with this 8753ES

 

On 3/18/19 3:32 PM, pianovt via Groups.Io wrote:
Yes, PNG is great for screen shots. The problem with the 8753D/ES
graphics is that the firmware guys didn't do the best job. They added a
graphics dump, but they only implemented jpg. To make it worse, you
can't download it via GPIB, it has to be stored to a floppy. At least, I
don't see a command to download the JPG via GPIB. If anyone here knows
how, please let me know.
Wow, I can't imagine that any engineer who was able to get hired by HP
wouldn't understand why JPG isn't appropriate for screen shots or other
line art. (or anything else that isn't a continuous-tone natural scene,
which is what JPG was designed for, and the only thing for which it
works well)

-Dave

--
Dave McGuire, AK4HZ
New Kensington, PA
Re: Understanding the 8753ES frequency loop

 

开云体育

Ah, so it starts at zero mA, although we are not interested (and likely not specced)below 3.8 GHz. 3.8 GHz output would then correspond to 3.8 * 23 mA on the main coil. Should the FM input be zero? ?I haven’t yet checked that. I wonder how far the FM input can move it if for example one if those transistors are bad.?

This would be an easy bench test of the YTO, or even easier in-instrument.?


Peter

On Mar 21, 2019, at 4:17 PM, pianovt via Groups.Io <pianovt@...> wrote:

It's a straight line, so pick any frequency you want. There is a non-linearity starting above 5.5 GHz or so. But, you are having problems at the low end, below 1 GHz rf out. That means the YTO is tuned to ~4.8 GHz when the rf output is 1 GHz.. Let's say you pick 4 GHz as a test point. The current should be 4 x 23 = 92 mA. If the actual coil sensitivity is at the upper limit (24 mA/GHz), then 96 mA.

Vladan

Re: Understanding the 8753ES frequency loop

 

It's a straight line, so pick any frequency you want. There is a non-linearity starting above 5.5 GHz or so. But, you are having problems at the low end, below 1 GHz rf out. That means the YTO is tuned to ~4.8 GHz when the rf output is 1 GHz.. Let's say you pick 4 GHz as a test point. The current should be 4 x 23 = 92 mA. If the actual coil sensitivity is at the upper limit (24 mA/GHz), then 96 mA.

Vladan
Re: NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B

 

You are thinking of the Dallas SmartSocket series, and it has
no identifying marks on it. It was used with a normal low power
CMOS RAM chip.

The OP's wording was somewhat awkward, but he doesn't have a
smart socket.

The OP has already said that his is an encapsulated Dallas NVRAM
that is installed in a socket.

He is safe to remove it, and read it with his EPROM programmer.

It will read just like a 6116, RAM chip. Different programmers
have different ways of reading the Dallas chip.

-Chuck Harris

Alan Melia via Groups.Io wrote:

Maybe not!! some of these Dallas devices have a battery in the socket to maintain the
contents. It may not be one of those but do check before removing anything. The
"socket" may actually be a header and the whole thing unplugged and read in a
programmer as if it was an EPROM. I last came across these in the 1990s using
prototyping/development kits. Others are rather "fat" 28-pin (0.6in.) IC shapes and
have an internal battery I think.

Alan
G3NYK
Looking to connect with other 4396B owners

 

This is my first post to the group, so hello everyone.? You've been a great resource when I've needed to search for information on prospective or actual TE purchases; thanks :)

I recently acquired an Agilent 4396B spectrum/network/impedance analyzer with all of the options (1D5 oven, 1D6 time-gated measurements, 010 impedance measurement) in non-working condition.? The main problem was some stressed SMD electrolytics on the A50 DC-DC converter board, as discussed in service bulletin 11.? There is also something odd in the source assembly, but it seems to be after the ALC power detector; current theory is the semi-rigid coax link from the output attenuator to the bulkhead N connector, or perhaps the N connector itself.? I'm documenting the repair here:



Looking ahead I have a few questions (and will undoubtedly have more as I dig into the analyzer's capabilities):

1) The calibration constants are stored in an EEPROM and updated over GPIB, but as far as I can tell the actual commands and format of the data are not documented.? The only approved way to update the calibration is to use an HP-UX program called "ADJ4396B" running on an ancient HP controller.? Is this likely to be a problem in the long run?? Should I consider sending the instrument out for calibration (assuming the cal lab even has access to this magic software)?? This is for home / hobby use only, so it likely doesn't matter, but I wonder if a window of opportunity is closing as these units get older and the last support is dropped.

2) Has anyone actually laid eyes (or camera) on the insides of the 43961A impedance test fixture?? I have no need for it except curiosity, but it would be fun to leverage the 010 software in my unit.? It could probably be a worthwhile learning experience to build something equivalent at lower frequencies.

3) Not a 4396B question per se, but what is the currently recommended GPIB interface solution in 2019?? I would prefer not to use any NI stuff or the VISA library, but if that's the price for being able to run useful third-party software (like KE5FX's phase-noise tool), I will.? Although in that case I would still prefer options which *can* work with the VISA library but can also work without them.? Cross-platform compatibility with Linux and Windows would be a plus.

Regards,
Mark
Re: NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B

 

Maybe not!! some of these Dallas devices have a battery in the socket to maintain the contents. It may not be one of those but do check before removing anything. The "socket" may actually be a header and the whole thing unplugged and read in a programmer as if it was an EPROM. I last came across these in the 1990s using prototyping/development kits. Others are rather "fat" 28-pin (0.6in.) IC shapes and have an internal battery I think.

Alan
G3NYK
NVRAM 28-Pin Encapsulated Package DS1230Y and 6811B

 

开云体育

Hello, I am doing maintenance on my instruments in my lab at the moment and I have a 6811B which poses a problem for me: the calibration constants are stored in a NVRAM whose date code is 1998, the device works well but no doubt it would be advisable to change this circuit without losing the data before the problems occur.

We are talking here about the Dallas DS1230Y (28-Pin Encapsulated Package), the integrated circuit is mounted on a socket.

?

I have a programmer Xeltek EPROM super pro Model 3000U available, and has in its library the DS1230Y.

I am not familiar with this kind of circuit, but from my understanding, I would have to carefully remove the DS1230Y from its socket and make a copy on my EPROM program.

?

Is it a good idea to try to do this, or there is a better solution?

Normally the DS1230Y should keep its data since there is an integrated battery.

?

Yves
Re: Understanding the 8753ES frequency loop

 

开云体育

Thank you.?

Is there a reference point and current?

Another words, X.XXX GHz at XXX.X mA?


Peter

On Mar 21, 2019, at 2:29 PM, pianovt via Groups.Io <pianovt@...> wrote:

Hi Peter,

You did a YTO swap, but it didn’t help, right? I guess, unless you know that your spare YTO is good, the result may not be conclusive. Here is some additional YTO information for you:

The main coil sensitivity is 23 mA/GHz? (+/- 1 mA/GHz). At lower frequencies (3.8 to 5+ GHz), the YTO is pretty linear. If you draw a straight line between 3.8 and 5.5 GHz, the deviation should be less than 3MHz, if that. The FM coil sensitivity is around 230kHz/mA. Maximum allowed FM coil current is 150mA.

Vladan

Re: Understanding the 8753ES frequency loop

 

Hi Peter,

You did a YTO swap, but it didn’t help, right? I guess, unless you know that your spare YTO is good, the result may not be conclusive. Here is some additional YTO information for you:

The main coil sensitivity is 23 mA/GHz? (+/- 1 mA/GHz). At lower frequencies (3.8 to 5+ GHz), the YTO is pretty linear. If you draw a straight line between 3.8 and 5.5 GHz, the deviation should be less than 3MHz, if that. The FM coil sensitivity is around 230kHz/mA. Maximum allowed FM coil current is 150mA.

Vladan
Re: HP5335A fan replacement

 

I added a low coil current 24V relay and grabbed 120VAC from elsewhere in the unit to power the AC fan.? To do so also allows a nice selection of a higher velocity fan if desired (and possibly lower noise level as opposed to the grinding noise of the DC fan).

Greg
Re: Understanding the 8753ES frequency loop

Pete Manfre
 

Me too… going on 4 weeks and just starting to get better.? ?Worst cold I have?ever had.?

Pete

On Thu, Mar 21, 2019, 2:00 PM Peter Gottlieb <hpnpilot@...> wrote:
Thank you.?

I’m still recovering from a real nasty flu/cold so everything is going really slowly here.?

I’m hoping that what I find is helpful to others as I have heard from another group member of a nearly identical problem. I’d like to post sufficient information such that anyone else running into this will have specific accurate numbers to compare against and hopefully to lead to more repaired units.?


Peter

On Mar 21, 2019, at 1:53 PM, Pete Manfre <pmanfre@...> wrote:

New board should be to you tomorrow.?

Pete wa2odo

On Thu, Mar 21, 2019, 1:32 PM Peter Gottlieb <hpnpilot@...> wrote:
Thank you. All this helps me piece together how the setup works. Right now I am collecting data and once it starts forming a coherent picture I will post it.?

The firmware plays a big part in this as well. For example, after default pretune values are set, test 48 creates individualized pretune values for that specific instrument. There is only so far that can compensate, though, and that’s apparently what I’m running into.? What I don’t yet know is whether the problem is on that board or if the YIG oscillator has drifted out of spec. It would be helpful to know just how far that firmware can compensate. I do see that my analog bus voltages are spot on, and seeing how your pretune voltage waveform is lower than mine, I still suspect a problem on my phase lock board. I have verified that the voltage to current converter is operating properly, and since the measurement resistor is verified well within its 1% tolerance, that the current through the YTO main coil should thus be within design tolerance as compared to the 1V/GHz signal. Thus any inability to be lower in voltage would have to be in the DAC, reference, voltage shift area that feeds the V/I converter. If however the replacement phase lock board has the exact same behavior I would have to look again at the YIG oscillator.?

Peter

On Mar 20, 2019, at 11:17 PM, pianovt via Groups.Io <pianovt@...> wrote:

Hi Peter,

The main and FM coil signals pass through the A3 ALC board like this:


<dummyfile.0.part>


The FM -? tap to the cavity oscillator is not part of the basic phase lock scheme, it's a spur avoidance fix. You don't need to waste time on studying that unless the fault is there.

Since you mentioned that the YTO is off (high?) by 200MHz, I think you should look at the main coil driver. It seems like something is preventing the main coil driver from delivering a low current. I am not aware of a PLL switch point at 1 GHz, but I have forgotten a lot about it so I may be wrong.

Vladan

Re: HP 8664A signal generator repairability

 

Thanks for all the hints on power meters! Duly noted.

As for the 8664, it passes all self tests. I also re-ran self cal now that the frequency reference is good and warm and everything seems to be working absolutely great. I negotiated a bit of refund back from the seller for the pain and suffering, and I have an order of rack handles on the way 2 4U sets (so I can put some handles on my 8569B microwave SA as well), and some extra 3U handles.

Sean
Re: Understanding the 8753ES frequency loop

 

开云体育

Thank you.?

I’m still recovering from a real nasty flu/cold so everything is going really slowly here.?

I’m hoping that what I find is helpful to others as I have heard from another group member of a nearly identical problem. I’d like to post sufficient information such that anyone else running into this will have specific accurate numbers to compare against and hopefully to lead to more repaired units.?


Peter

On Mar 21, 2019, at 1:53 PM, Pete Manfre <pmanfre@...> wrote:

New board should be to you tomorrow.?

Pete wa2odo

On Thu, Mar 21, 2019, 1:32 PM Peter Gottlieb <hpnpilot@...> wrote:
Thank you. All this helps me piece together how the setup works. Right now I am collecting data and once it starts forming a coherent picture I will post it.?

The firmware plays a big part in this as well. For example, after default pretune values are set, test 48 creates individualized pretune values for that specific instrument. There is only so far that can compensate, though, and that’s apparently what I’m running into.? What I don’t yet know is whether the problem is on that board or if the YIG oscillator has drifted out of spec. It would be helpful to know just how far that firmware can compensate. I do see that my analog bus voltages are spot on, and seeing how your pretune voltage waveform is lower than mine, I still suspect a problem on my phase lock board. I have verified that the voltage to current converter is operating properly, and since the measurement resistor is verified well within its 1% tolerance, that the current through the YTO main coil should thus be within design tolerance as compared to the 1V/GHz signal. Thus any inability to be lower in voltage would have to be in the DAC, reference, voltage shift area that feeds the V/I converter. If however the replacement phase lock board has the exact same behavior I would have to look again at the YIG oscillator.?

Peter

On Mar 20, 2019, at 11:17 PM, pianovt via Groups.Io <pianovt@...> wrote:

Hi Peter,

The main and FM coil signals pass through the A3 ALC board like this:


<dummyfile.0.part>


The FM -? tap to the cavity oscillator is not part of the basic phase lock scheme, it's a spur avoidance fix. You don't need to waste time on studying that unless the fault is there.

Since you mentioned that the YTO is off (high?) by 200MHz, I think you should look at the main coil driver. It seems like something is preventing the main coil driver from delivering a low current. I am not aware of a PLL switch point at 1 GHz, but I have forgotten a lot about it so I may be wrong.

Vladan

Re: Understanding the 8753ES frequency loop

Pete Manfre
 

New board should be to you tomorrow.?

Pete wa2odo

On Thu, Mar 21, 2019, 1:32 PM Peter Gottlieb <hpnpilot@...> wrote:
Thank you. All this helps me piece together how the setup works. Right now I am collecting data and once it starts forming a coherent picture I will post it.?

The firmware plays a big part in this as well. For example, after default pretune values are set, test 48 creates individualized pretune values for that specific instrument. There is only so far that can compensate, though, and that’s apparently what I’m running into.? What I don’t yet know is whether the problem is on that board or if the YIG oscillator has drifted out of spec. It would be helpful to know just how far that firmware can compensate. I do see that my analog bus voltages are spot on, and seeing how your pretune voltage waveform is lower than mine, I still suspect a problem on my phase lock board. I have verified that the voltage to current converter is operating properly, and since the measurement resistor is verified well within its 1% tolerance, that the current through the YTO main coil should thus be within design tolerance as compared to the 1V/GHz signal. Thus any inability to be lower in voltage would have to be in the DAC, reference, voltage shift area that feeds the V/I converter. If however the replacement phase lock board has the exact same behavior I would have to look again at the YIG oscillator.?

Peter

On Mar 20, 2019, at 11:17 PM, pianovt via Groups.Io <pianovt@...> wrote:

Hi Peter,

The main and FM coil signals pass through the A3 ALC board like this:


<dummyfile.0.part>


The FM -? tap to the cavity oscillator is not part of the basic phase lock scheme, it's a spur avoidance fix. You don't need to waste time on studying that unless the fault is there.

Since you mentioned that the YTO is off (high?) by 200MHz, I think you should look at the main coil driver. It seems like something is preventing the main coil driver from delivering a low current. I am not aware of a PLL switch point at 1 GHz, but I have forgotten a lot about it so I may be wrong.

Vladan

Re: Understanding the 8753ES frequency loop

 

开云体育

Thank you. All this helps me piece together how the setup works. Right now I am collecting data and once it starts forming a coherent picture I will post it.?

The firmware plays a big part in this as well. For example, after default pretune values are set, test 48 creates individualized pretune values for that specific instrument. There is only so far that can compensate, though, and that’s apparently what I’m running into. ?What I don’t yet know is whether the problem is on that board or if the YIG oscillator has drifted out of spec. It would be helpful to know just how far that firmware can compensate. I do see that my analog bus voltages are spot on, and seeing how your pretune voltage waveform is lower than mine, I still suspect a problem on my phase lock board. I have verified that the voltage to current converter is operating properly, and since the measurement resistor is verified well within its 1% tolerance, that the current through the YTO main coil should thus be within design tolerance as compared to the 1V/GHz signal. Thus any inability to be lower in voltage would have to be in the DAC, reference, voltage shift area that feeds the V/I converter. If however the replacement phase lock board has the exact same behavior I would have to look again at the YIG oscillator.?

Peter

On Mar 20, 2019, at 11:17 PM, pianovt via Groups.Io <pianovt@...> wrote:

Hi Peter,

The main and FM coil signals pass through the A3 ALC board like this:


<dummyfile.0.part>


The FM -? tap to the cavity oscillator is not part of the basic phase lock scheme, it's a spur avoidance fix. You don't need to waste time on studying that unless the fault is there.

Since you mentioned that the YTO is off (high?) by 200MHz, I think you should look at the main coil driver. It seems like something is preventing the main coil driver from delivering a low current. I am not aware of a PLL switch point at 1 GHz, but I have forgotten a lot about it so I may be wrong.

Vladan

Re: HP 3563A (3562A) A9 FFT

morestainless
 

The 2nd FFT board arrived, sourced less than 1hr from here, and it is a good board.? All self tests passed.? The 3563A is working!??


On Tue, Mar 19, 2019 at 12:18 PM, morestainless via Groups.Io
<lancelotburt@...> wrote:
The signals and voltages appear to be ok.? Some of the IC pin signatures on the GI chips were correct, and they were all stable.? The board passes all fft tests aside from the global interface and rom.? The rom test is dependent upon the GI.

I just returned the 1st ebay fft board (cpu dead) and the 2nd is on the way.


On Mon, Mar 18, 2019 at 2:23 PM, morestainless via Groups.Io
<lancelotburt@...> wrote:
Chuck,

Thanks for that bit of wisdom.? I had checked filter caps, clock, and voltages before.? All within spec.? The electrolytic and bypass caps on the board are good.? I'll check all the fft signal waveforms then.? Guess that's why they are described in the manual.


On Mon, Mar 18, 2019 at 1:08 PM, Chuck Harris
<cfharris@...> wrote:
Two things:

1) signature analysis can fail if clocks and dividers
? aren't working right.
2) clocks and dividers can fail if power supply bypass
? capacitors aren't low enough ESR.

Before you condemn your board, do make sure that the
board's bulk bypass capacitors, and any filters that feed
them are good.

I have fixed several boards from this family of DSA's where
the only problem was bad electrolytic capacitors.

-Chuck Harris


morestainless via Groups.Io wrote:
> Anybody have a working A9 FFT board for this machine they would part with?? 3562A and 3563A? use the same board.? Signature analysis shows the global bus chips U511 - U518 are bad as are the two coefficient ROM's - U315 and U317.? Firmware images would also be a possibility as the interface chips are cheap enough.
>
>
>
>



Re: HP 8664A signal generator repairability

 

开云体育

Seconded,? I have gotten bit by the 2nd or 3rd harmonic even on a good meter.? Bird is considered a 5 or 10% meter at best great for tuning bad for accuracy

?

Regards,

?

Stephen Hanselman

Datagate Systems, LLC

3107 North Deer Run Road #24

Carson City, Nevada, 89701

(775) 882-5117 office

(775) 720-6020 mobile

s.hanselman@...

a Service Disabled, Veteran Owned Small Business

DISCLAIMER:

This e-mail and any attachments are intended only for use by the addressee(s) named herein and may contain legally privileged and/or proprietary information. If you are not the intended recipient, any dissemination, distribution or copying of this e-mail and any attachments is strictly prohibited. If you have received this e-mail in error, please immediately notify me and permanently delete the original and all copies and printouts of this e-mail and any attachments.

?

?

?

From: [email protected] <[email protected]> On Behalf Of alwyn.seeds1
Sent: Thursday, March 21, 2019 3:35 AM
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] HP 8664A signal generator repairability

?

Dear All,

?

"From:?Bob Albert
Date: Wed, 20 Mar 2019 17:28:34 PDT?

?

For a decent power meter you do NOT want a Bird.? They are pretty sloppy."

?

Sorry for using the vague term “decent power meter”. I meant something like an HP 435/436 with an 8481A measurement head.

?

The Bird instruments are intended for measuring rather larger RF powers and, as Bob says, do not offer the accuracy required for testing a signal generator.

?

While writing, a tip to avoid the mistake I once made. Power meters are, of course, broadband. Therefore if the signal to be measured has significant harmonic content an error in measuring the fundamental power will result. Forgetting about this, I was puzzling why the Cal. outputs of my 8560 series and 8590 series spectrum analysers measured differently. Then I realised that the 8590 Cal. source has strong harmonic output, whereas the 8560 series source does not.

?

Similarly, some signal generators that use frequency doublers produce strong half-frequency outputs which would cause an error when checking output power on the highest frequency range with a power meter.

?

Regards,

?

Alwyn

?

_____________________________________________________

?

Alwyn Seeds, Director
SynOptika Ltd.,
114 Beaufort Street,
London,
SW3 6BU,
England.

Tel.: +44 (0) 20 7376 4110


SynOptika Ltd., Registered in England and Wales: No. 04606737
Registered Office: 114 Beaufort Street, London, SW3 6BU, United Kingdom.

_____________________________________________________

?
Re: Signal Generator Comparison Chart ?

 

I live in Ontario Canada and get heavy items shipped to the UPS Store in Ogdensburg NY, sometimes saving as much as $400 shipping!
They charge $5 per package for 10 or 15 days, check. It used to be a week.??
It means 3 hours drive each way but my wife and I make a trip of it.
PeterB

On Wed, Mar 20, 2019 at 10:56 PM amirb <amir.borji@...> wrote:
I have also been in the market for a 26GHz SG for a while with no luck. Although I have to say the biggest issue for me
has been the sellers not shipping to Canada. I came close to getting a 8673B for $150 but then the seller finally decided he wouldn't ship to Canada...

with regard to models:
8673B (has modulations) and 8673G (strip down version of B with no modulation) go from 2GHz-26.5GHz and at least for my purpose they are fine
both have excellent specs and they are synthesized signal generators. 8673D is also an option (0.05G-26.5G) but it is huge like a tank

the best overall in my opinion is 8340B or 8340A (no FM modulation) they go down to 10MHz and up to 26.5GHz with excellent
specs on accuracy and noise and they are standard calibration sig gens for spectrum analyzers.

remember 8350B is a sweep generator and the oscillator modules that come with it are NOT synthesized sig gens. they are generally poor on stability and accuracy
and that's why they have a low frequency resolution, too, I guess but their amplitude is stabilized in an ALC loop
I wouldn't go down that path unless you are in a hurry for a particular project

Next comes Wiltron synthesizers 67xx. The one I have been looking for is 6759B which is 10MH - 26.5GH synthesized with very good specs. very close to 8673B actually
their service manual is also available. 6769 goes up to 40GHz

and finally Gigatronics 1026 and 7100 and 7200. they all synthesize the frequency and have very good specs but not sure about service manual availability






On Wed, Mar 20, 2019 at 04:35 PM, Tim Tuck wrote:
Hi all,

I was wondering if there is a sig gen comparison chart somewhere.
Googling around I only found a pdf from Keysight of their latest generators.

Personally I'm in the market for something that goes to 26Ghz ( Id like
to go higher but the $'s start to get crazy for a hobbyist!) and I've
been looking at 8673's but they're not the only ones out there.

Scanning ebay for kit, I keep bumping into HP model numbers I've not
heard of before and then run down that rabbit hole investigating the
model. It'd be nice if there was a definitive list of all
HP/Agilent/Keysight sig gens to look at.

Does such a thing exist ?

thanks

Tim

de VK2XAX
Re: 8970b

kevin kearns
 

Thanks Tom, I will try it! Kevin

----- Original Message -----
From: "Tom Holmes" <tholmes@...>
To: <[email protected]>
Sent: Thursday, March 21, 2019 1:18 AM
Subject: Re: [HP-Agilent-Keysight-equipment] 8970b


Use SP 1.3, since you have a more or less fixed IF frequency. Page 3-128 in
the 8970S manual is pretty clear about that. Also be sure to use SP 3.0,
which sets the IF frequency. Since you probably aren't doing a swept NF
measurement, ignore that part of the procedure. Since the output of the
noise source is within range of your 144 MHz input, and the IF at 30 MHz is
within the range of the 8970B, you can set this up just like doing a preamp,
except that mode 1.3 allows you to tell the system to use the ENR of the
noise source at 144 MHz, while listening at 30 MHz. During CAL, the 8970B
listens at 144 to get the source power levels, then during measurements,
listens at 30 MHz.

You might try, as an experiment, just using the 8970B in its SP 1.0 mode.
The input an output are not far apart and the source is pretty flat, as is
the receiver in the 8970B. You might find you get an almost identical result
to SP 1.3.

Yeah, the manual can be aggravating at times; it can take a lot of digging
to find what you need to know.

Hang in there, you'll get it working.

Tom Holmes, N8ZM
56301 - 56320 of 151491