Re: E4407B strange peak shapes at low RBW
You will need to go in and adjust your Xtal and LC filters.? Not hard, just a pain.
Richard
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Hello Everyone,
I am working on my E4407B and found that it has funny peak shape when I use low Resolution Bandwidths.
The shape is not collected into one peak, instead its smeared as in the pictures.
The bad shapes occur at RBW 300kHz, 100kHz. I don't think its there at 30kHz, but I could be wrong..
Anybody have any clue?
  
Best regards
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Thanks Lothar.
All understood.?? Diode based I understood and knew already.? After
all, some of the usage examples are for sweeping filters much as a
scalar analyser does things.
There seems to be even less info about the 85037 detectors than the
86200 series!?? But a common "feature" is a lower working frequency
bound of 10 MHz.
73.
??? Dave.
Re:-
The 86200 is a entirely different architecture as the regular HP
sensors , it is a diode based sensor that contains correction
constants inside a EEPROM , if I remember they were based on the
85037 detectors rather than regular HP sensors
--
Created on and sent from a Unix like PC running and using free and open source software:
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E4407B strange peak shapes at low RBW
Hello Everyone, I am working on my E4407B and found that it has funny peak shape when I use low Resolution Bandwidths. The shape is not collected into one peak, instead its smeared as in the pictures. The bad shapes occur at RBW 300kHz, 100kHz. I don't think its there at 30kHz, but I could be wrong.. Anybody have any clue?    Best regards
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Re: HP 8662A Power up - overvoltage shutdown
Hi Tony
?Use new Tantalums, but double the voltage ratings if at all possible,?
G Edmonds
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Re: HP8920A display onto computer monitor
Use a gbs8220 board with a sync separator lm1881.? Enviado do meu Tele-Movel
There is a video out on the back panel. The manual says that you need a 'multisync monitor'. This is a composite signal, but I don't know what the scan frequencies are. There are some composite lcd monitors for CCTV that work on several standards, but I haven't tried them yet. I have the 8922M which is similar and I also want a larger display. It would also be nice to be able to convert the video into a printable graphic.
I wonder if anyone has came up with a way to get the
HP8920A to display to a standalone computer monitor
and can you tell me what I need and how to do it.
All help is greatly appreciated, thanks.
Fred
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Re: HP8920A display onto computer monitor
There is a video out on the back panel. The manual says that you need a 'multisync monitor'. This is a composite signal, but I don't know what the scan frequencies are. There are some composite lcd monitors for CCTV that work on several standards, but I haven't tried them yet. I have the 8922M which is similar and I also want a larger display. It would also be nice to be able to convert the video into a printable graphic.
I wonder if anyone has came up with a way to get the
HP8920A to display to a standalone computer monitor
and can you tell me what I need and how to do it.
All help is greatly appreciated, thanks.
Fred
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Re: HP 8662A Power up - overvoltage shutdown
Gerald,
What do you recommend replacing them with - new tantalums?
(It would be a long weekend!)
thanks
Tony
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HP8920A display onto computer monitor
I wonder if anyone has came up with a way to get the
HP8920A to display to a standalone computer monitor
and can you tell me what I need and how to do it.
All help is greatly appreciated, thanks.
Fred
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Re: HP 8116A woes with E42 error
Thanks for the help fellas. Really appreciate it. Will target Q502 first and let ya know how it goes. Probably won't be until Friday or next weekend before I can get after it. Plus not sure if I have a PNP for replacement. Will have to look.
Will keep you updated.
Thanks,
David
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Re: HP 8662A Power up - overvoltage shutdown
I recommend another weekend and replace all tear drop tantalums, it will happen again and again over time if you do not remove all.
Regards
Gerald
VK3GM
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Re: HP 8662A Power up - overvoltage shutdown
WB8TSL:
.... The 8663 supply is pretty much the same.
The 20 V reg is pretty simple and can be traced out if needed. But check that the 20 V is not shorted to ground. The smoke makes me think someplace in the unit a tantalum has turned very black.
The supply senses current and does limit.?
Good luck
That helped, my 8662A works again. It did cost me most of the weekend. Some
50 screws are still to be re-inserted and my fingertips are sore because of the
many sharp edges on the SMCs.
It wasn't the power supply. It was one of these light-blue tantalums on A4A3.
I could not find the A4A3 drawing. In the 8663A this is something unrelated.
I wanted to see the source of the black smoke but could not find it, although
I opened all the plug-ins. The shorted tantalum looked completely innocent.
I Widlarized it carefully.
In one of the x reference lists, the linear regulators were translated as CA3020,
a double long tail pair. It is LM204 / LM205.
As a side effect, this 0-160MHz-320MHz-480MHz-bug is gone. No idea why.
I also replaced the incontinent NiCd battery block. It is the same type of
block that used to be in my HP-35 in a previous life. For the moment,
these are Eneloops until I get NiCds. Those are quite rare here now.
I also used a new battery holder.
Thanks to all and 73,
Gerhard DK4XP
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Re: E4418B power supply schematic?
Hi Tom thank you for the link to the power supply
I have uploaded it to the E4418-9 file along with service and user information
Regards Paul B
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Tom B Sent: 30 May 2022 18:27 To: [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] E4418B power supply schematic? Hi Razvan, I don't have a schematic, but mine has an Artesyn NFN40-7608. The datasheet is here. Is the standby light on, or do you get nothing? Tom On 5/30/2022 10:49 AM, Razvan wrote: Hey everyone,
Is there any information out there on the power supply used in these
units? Mine appears to have died (I can't measure any output), and I
can't find the schematic in the CLIP files.
The full part number of the PSU seems to be JW 1287, JW being the
manufacturer.
This isn't the first time it failed. Many years ago a resistor went
open, but I don't remember how I troubleshooted that, and I didn't
take any notes...
Cheers,
Razvan
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Re: HP 8116A woes with E42 error
On Mon, May 30, 2022 at 11:35 PM, Swiss wrote:
As far as checking Q502 in circuit, a diode check indicates that it is conducting, However its values are higher then that of Q501. Roughly from 1V to 1.5V. Whereas Q501 is .7 V drop. It's hard to say as the capacitors on their bases are charging up.
I can assure you: A steady-state voltage of approx. 10.5V (mind the polarity: Q502's emitter 10.5V more positive than its base, as may be concluded from 3) and 4)) between Q502's emitter and its base means its B-E-diode is non-existent. - Perhaps the trace between the cathode of CR502 and the base of Q502 or some other connection is gone? - Maybe there's an NPN transistor where a PNP should be at Q502? The capacitors at the bases of Q501 and Q502 are negligible when measuring steady DC voltages. Not sure what you mean by "However its values are higher then that of Q501. Roughly from 1V to 1.5V.". 1V or even 1.5V across a healthy B-E junction of Q502 is wrong; it should be near 0.7V max. Raymond
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Re: HP 8116A woes with E42 error
On Mon, May 30, 2022 at 02:35 PM, Swiss wrote:
I double checked my DC measurements for the cathode of CR502 and the emitter of Q502 and they were the same as above.
Put a scope on pin 6 of U502, and there is minimal AC. 52 mV max. These are spurious signals from the lights in the room due to the switch mode LEDs above. The Average AC was about 5mV. Sometimes alittle less.Not sure if this is significant or not.
Checked the resistance from pin 6 U502 to the anode of CR502 and measured 248.54 ohms. R509 is good to go.
As far as checking Q502 in circuit, a diode check indicates that it is conducting, However its values are higher then that of Q501. Roughly from 1V to 1.5V. Whereas Q501 is .7 V drop. It's hard to say as the capacitors on their bases are charging up.
---- If 1V-1.5V measurements are with no power applied then Q502 is bad as Raymond also suggested. |Vbe| shouldn't exceed ~ 0.7V even in-circuit if power is not applied. Even with power applied I can't think of a case where multimeter can measure 1.5V forward bias voltage. I don't know how difficult is to remove Q502 but removing it and measuring it by itself will probably show a faulty Q502.? Ozan
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Re: HP 8116A woes with E42 error
I double checked my DC measurements for the cathode of CR502 and the emitter of Q502 and they were the same as above.
Put a scope on pin 6 of U502, and there is minimal AC. 52 mV max. These are spurious signals from the lights in the room due to the switch mode LEDs above. The Average AC was about 5mV. Sometimes alittle less.Not sure if this is significant or not.
Checked the resistance from pin 6 U502 to the anode of CR502 and measured 248.54 ohms. R509 is good to go.
As far as checking Q502 in circuit, a diode check indicates that it is conducting, However its values are higher then that of Q501. Roughly from 1V to 1.5V. Whereas Q501 is .7 V drop. It's hard to say as the capacitors on their bases are charging up.
I'm going to have to do surgery at some point, but I guess a good goal is to narrow it down as much as possible. Don't just like changing parts willy nilly. If U502 and Q502 are in question, I can change those one at a time and see how things go. I can also check the other 8116A. It's probably going to be the end of next week before I can do the above. Will be tied up till next Friday after this afternoon.
Thanks for the help and responses,
David
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Re: HP 3465A offset when input shorted
Quick update on this one, mostly replying for completion. I located the suggested 2N4117A from Langrex here in the UK for a measly ?3.50 which was acceptable coin for this DMM. Arrived today. Did a couple of checks to make sure it was indeed feasibly a FET and wired it as a diode and tested it successfully. This was then substituted in, the clamp tested and the unit recalibrated in DC only to start with.?The meter now has no offset and zeroes correctly. I did a basic DC calibration and ohms calibration against my 34401A and it's spot on now. I will do the AC calibration once I've obtained some cables.  Thanks all for the assistance - one more bit of HP kit back in action! Best regards, Chris
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Re: HP 8116A woes with E42 error
On Mon, May 30, 2022 at 10:48 PM, Raymond Domp Frank wrote:
I assumed you were looking with a minimal amplitude AC signal. If incorrect, you're unnecessarily complicating things and making measurements with a DC meter essentially useless.
... as Ozan correctly says. Raymond
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Re: HP 8116A woes with E42 error
On Mon, May 30, 2022 at 09:29 PM, Raymond Domp Frank wrote:
The combination of 3) and 4) would indicate Q502 has open base-emitter
I assumed you were looking with a minimal amplitude AC signal. If incorrect, you're unnecessarily complicating things and making measurements with a DC meter essentially useless. Raymond
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Thanks Jim.? I don''t know where to look for the input to the attenuator so I better start reading the manual.? Your diagnosis is what I hope is the problem, since repairing that may not be as major.? I recall determining that the output amplifier transistors are good.
Bob
On Monday, May 30, 2022, 11:40:15 AM PDT, Jim Summers <kd7f@...> wrote:
I sounds like there may be a problem with the reverse power protection.? There are PIN diodes in series with zener diodes to ground in the protection circuit and it sounds like perhaps one of the zeners has shorted out - probably from application of reverse power above the specification.?
If you were to look at the signal at the input to the attenuator and you see no distortion at high levels (+10dBm and above) then it is probably the reverse power protection circuitry that is at fault...? It is the first thing seen coming in from the front panel connector and I believe it is in one of the attenuator enclosures.?
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The 86200 is a entirely different architecture as the regular HP sensors , it is a diode based sensor that contains correction constants inside a EEPROM , if I remember they were based on the 85037 detectors rather than regular HP sensors
?
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From: [email protected] < [email protected]>
On Behalf Of Dave_G0WBX via groups.io
Sent: Monday, May 30, 2022 3:22 PM
To: [email protected]
Subject: [HP-Agilent-Keysight-equipment] HP 86200B detectors.
?
Hi.
Apologies if I've asked this here before, but the grey cell doesn't recall doing so...
I have two 86200B 50 Ohm 10 MHz to 3 GHz detector probe assemblies (with cables) that came with my slightly sick but still usable 8714B VNA.
Nothing wrong with them they both work OK (and confirm the issue with the VNA is the source not the RX, but that's another story.)
Question:
Which (if any) HPAK Stand Alone Power Meters, can use these probes as sensors?
Or has anyone created a stand alone device as a project, or an adapter for one of the common power meters?
I have not found any technical info about them (other than the basic specifications) anywhere online.
Just wondering if they can be used independently of the 8714, as low power sensors?
Cheers to All.
Dave G8KBV/G0WBX
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Alexandre Souza
Michael A. Terrell
Paul Bicknell