External Clock board for 332xx series
Hi fellows,
?
Some years ago I made a external clock input board for my HP/Agilent 33220A.
?
I offer two remaining PCB¡¯s few weeks ago on this site and they immediately gone.
My question is, whether there is any more interest in this or to archive this project?
On my side, to make it cost effective, more than 7 orders are required. The price would be 99USD including the shipping cost to US or Europe and will take about 4-5 weeks to build-up (holiday season coming¡).
?
Design are based on original Agilent 33220-80001 (33220-66503) board and compatible with 332xx series of function / arbitrary waveform generators, but slightly modified.
Input impedance is 50ohm AC coupled, DC isolated from instrument housing and sensitivity of -13 +/-2 dBm. Input level for optimal jitter/phase noise is between 0 and 20dBm. Board is only 10MHz input, no loop back output!
?
Picture of board installed in my 33220a is attached. New revision will have MCL or Coilcraft 1:1 input isolation transformer.
?
Regards,
Milan
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Re: 8566 to measure 100W FM transmitter
What are you trying to measure, the fundamental, modulation, harmonics or what? #this will determine what bandwidth and accuracy you need
Is the measurement off-air or into a dummy load. If a load a power attenuator is best. if off-air some kind of coupler will be required. a resistive tap like
? or
would do and is reasonably broad band.
If looking at harmonics you will probably have to put a notch filter in the sampled ignal to reduce the carrier level and prevent spurious signals being generated in th analyser.
Robert G8RPI.
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Re: 8566 to measure 100W FM transmitter
First of all you must be very strong. The 8566 A or B is somewhat over 100 pounds and very bulky, if you have to take it to the transmitter. I have one of each and try to never move them.
I would keep the input power below one half watt on the 8566 input, to be safe. Never put in zero dB attenuator on the analyzer!
You will either need a large 50 ohm attenuator of at least 40 dB, with an additional low power 10 dB attenuator to sample the transmitter and protect the spectrum analyzer. That is what I have on the bench.
The other way to measure the transmitter is to use a high power directional coupler in addition to a small attenuator on the forward coupled arm, for insurance.
I routinely measure two 21 kW FM transmitter, but they have a built-in 55 dB directional coupler. However, I always use an additional attenuator at the spectrum analyzer, just in case.
If you are just looking at a SSB transmitter, at a very narrow dispersion, you probably can use just a test lead. If you are just interested in relative readings, such as close-in distortion, carrier or unwanted sideband suppression in a Single Sideband transmitter, that will work well.
Stuart K6YAZ
Los Angeles, California
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Re: 8566 to measure 100W FM transmitter
Why not just use a foot
long piece of coax, any kind will do, make a pig-tail out of
the far end and attach an alligator clip to the center
conductor and just lay it on the bench. It will make a dandy
RCV antenna.
If you are any where
near the transmitting antenna and the transmitter is
outputting 100W of RF at VHF you will have plenty of RF signal
to sample. If need be bring along either an adjustable step
attenuator and a couple 20dB or 40 dB fixed attenuators in
case the level is still too strong.
I have done this dozens
of times to monitor my own RF signal at various frequencies
when I do not want to go to the trouble of connecting up a
directional coupler and a step attenuator. You do not need to
go to the trouble to capacitive couple to the actual
transmission line of the transmitter.
Gedas, W8BYA
Gallery at
Light travels faster than sound....
This is why some people appear bright until you hear them speak.
On 5/23/2019 2:56 PM, DW wrote:
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Show quoted text
I have a 8566 and I need to sample the signal of a 100W FM
transmitter. I haven't seen the transmitter but I was told the
following below.
Take a piece of wire and attach it to the end of the cable that
will go to the 8566. One end will go to the center conductor and
the other will go through a resistor to the shield of the cable.
This wire will loop once around the transmission line. So far I
made two various wires, one with a 400 ohm resistor and another
with a 200 ohm resistor. I will take a 2W attenuator with me for
good measure. Any thoughts on this, thanks. I ask this as I'm
being cautious about the input level to the 8566 as I know it
doesn't take much to destroy the front end of a spectrum analyzer.
Thanks
|
Re: 8566 to measure 100W FM transmitter
I built one of these:
You might want to use a larger resistor and make it a 50 dB tap. I use that for my amp output. Of
course you have to calibrate it using a SA and TG or a VNA because the
attenuation is not exact, but I have had good results through HF feeding
the output to a SA or 50 ohm scope input.
Regards,
Mark W7MLG
I should add the 100W will be driven to an antenna on a tower, I don't have a sampler so I'm limited to what I can sample, hopefully the transmitter has a sample port
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Re: 8566 to measure 100W FM transmitter
I should add the 100W will be driven to an antenna on a tower, I don't have a sampler so I'm limited to what I can sample, hopefully the transmitter has a sample port
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Re: 8566 to measure 100W FM transmitter
I believe it is 99.1mhz I have a 90dB manual step attenuator so that should help some along with a resistor to help pad down the levels, how hot do sample ports usually run on small FM transmitters I wonder. Thanks for the replies
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Re: 8566 to measure 100W FM transmitter
Do you need to measure it on the air? What frequency is the Tx?
Is there a sample port on the transmitter?
Regards
On 5/23/2019 2:56 PM, DW wrote:
I have a 8566 and I need to sample the signal of a 100W FM
transmitter. I haven't seen the transmitter but I was told the
following below.
Take a piece of wire and attach it to the end of the cable that
will go to the 8566. One end will go to the center conductor and
the other will go through a resistor to the shield of the cable.
This wire will loop once around the transmission line. So far I
made two various wires, one with a 400 ohm resistor and another
with a 200 ohm resistor. I will take a 2W attenuator with me for
good measure. Any thoughts on this, thanks. I ask this as I'm
being cautious about the input level to the 8566 as I know it
doesn't take much to destroy the front end of a spectrum analyzer.
Thanks
|
Re: 8566 to measure 100W FM transmitter
the best Thing woud be to use a power attenuator e.g. 40 dB /500 W plus another 10 dB attenautor between the? Output of the poer att and Input of the SA. Remember 100 W = +50 dBm, so an overlal attenuation of 50 dB (40 dB + 10 dB) will give You 0 dBm = 1 mW at the Input of Your SA, save enough for Yoru Instrument.
Henning Weddig
-----Urspr¨¹ngliche Mitteilung-----
Von: DW <wilson2115@...>
An: HP-Agilent-Keysight-equipment < [email protected]>
Verschickt: Do, 23. Mai 2019 20:56
Betreff: [HP-Agilent-Keysight-equipment] 8566 to measure 100W FM transmitter
I have a 8566 and I need to sample the signal of a 100W FM transmitter. I haven't seen the transmitter but I was told the following below.
Take a piece of wire and attach it to the end of the cable that will go to the 8566. One end will go to the center conductor and the other will go through a resistor to the shield of the cable. This wire will loop once around the transmission line. So far I made two various wires, one with a 400 ohm resistor and another with a 200 ohm resistor. I will take a 2W attenuator with me for good measure. Any thoughts on this, thanks. I ask this as I'm being cautious about the input level to the 8566 as I know it doesn't take much to destroy the front end of a spectrum analyzer. Thanks
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Re: WTB AMI/Mostek MK6220N RAM Chip
Adrian I guess only time will tell. But when I was getting the chip to temporarily work with heat, I barely put the tip of the soldering iron for more than 2-3 seconds on a pin solder junction, not really enough to be able to heat up any of the stuff that was underneath. Or maybe there was a bit between two adjacent pins, but I recall very briefly applying heat to different pins and always getting the same result. Now the very last thing left is to fix is the display, which has a faulty a-segment on the last right most digit. I could live with it, but it would be nice to see it whole again.
Alex
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8566 to measure 100W FM transmitter
I have a 8566 and I need to sample the signal of a 100W FM transmitter. I haven't seen the transmitter but I was told the following below.
Take a piece of wire and attach it to the end of the cable that will go to the 8566. One end will go to the center conductor and the other will go through a resistor to the shield of the cable. This wire will loop once around the transmission line. So far I made two various wires, one with a 400 ohm resistor and another with a 200 ohm resistor. I will take a 2W attenuator with me for good measure. Any thoughts on this, thanks. I ask this as I'm being cautious about the input level to the 8566 as I know it doesn't take much to destroy the front end of a spectrum analyzer. Thanks
|
Obviously I took on more than I can handle. I was hoping a few interested fellows would come over and we could work out some deals. That does not seem to be happening. I am overwhelmed by emails, only a few with offers and the others asking how much, even though I asked for offers. Also, most are interested in the smaller items like horns and so on. This essentially means that I need to go through all of the small stuff to find specific requests. If I am going to do that, I might as well start selling items as I go through them. More than likely I will strip all of the heavy stuff and sell the essential pieces. So, here are three items for sale to start that are easily mailable. ? HP Harmonic mixers ¨C ? 11970K $200 11970A $250 11970U $550 ? If you want all three, I will accept $800 plus shipping. I will also consider offers on the others. As soon as these sell, I will list other items or wait a week and list other items. Thanks & 73 ¨C Mike ? ? ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ?
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From: Mike Feher <n4fs@...> Sent: Tuesday, May 21, 2019 2:16 PM To: ' [email protected]' < [email protected]> Subject: TE FS - ? Hi all ¨C ? Since I hardly ever use my lab any more, I decided to sell most of its contents. Unfortunately I am unable to ship heavier items due to physical limitations here. Consequently, if you would like to get something it is best if you pay me a visit. The more you take, the better the price, HI. Small items I can ship or even place on eBay. PP is fine with me. Any interest then please call or send me a direct email at n4fs@... . You can also try calling on the number below, however I do not have an answer machine set up on it. At the following link you can see 64 pictures, some not that great, taken inside the lab. In addition I also have a 2000 sq. foot basement, a 600 sq. foot garage and a 1000 sq. foot shed all full of stuff including loads of TE. Looking for offers until I place the smaller stuff on eBay. Thanks & 73 ¨C Mike ?
? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ?
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Re: WTB AMI/Mostek MK6220N RAM Chip
Ok, so my theory is that the stuff you cleaned up under the chip was hygroscopic and when damp was conductive enough to cause a problem.
Re-soldering the IC pins dried it out a bit allowing things to work for a while. Now you've cleaned it up it's good for the next 45 years....?
Adrian
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On 5/23/2019 1:56 PM, Alex wrote: Here is an update on the removal of the RAM chip from the main board.
The IC was unsoldered with soldapult pump and plenty of liquid flux. To clear some of the vias and since most pins where resting on the inner walls of the vias, had to first center them in the hole and then retry clearing it out of solder. On the top side of the board had to use solder wick to clear some excess solder holding some of the pins to the board. It took a while but eventually managed to gently pry the chip loose.
There was indeed still some corrosion left on and between 3 of the 4 traces that run under the IC, but very light not really much. Cleaned up traces with 91% IPA, and a Q-tip. The IC body itself seemed clean on the bottom and in between the pins, but just in case gave it a gentle brushdown with IPA as well. Also cleaned up the residual flux left on the board. Happned to have two 10-pin low-profile socket strips (these cost almost 50 cents/pin!) so trimmed then down to 8 pins each and mounted the RAM chip to align all the pins properly and then soldered the socket. Only soldered the pins that are actually in use which on this chip is only 8 out of 16. Just in case to make it easier if in the future I ever needed to remove the socket.
After powering up the calculator it worked 100%. It certainly must be due to residual heat from the desoldering/resoldering operation.
30 minutes later it still works. Completely removed power and let it sit for about 3 hours, test again: still working. Put the board back into the calculator case and reassembled it, put in the battery pack: still going.
It is now almost 20 hours after the repair and the calculator is still working 100%. Last night gave it a through workout to test all functions, and ran a short program. Everything worked.
Only question is, will this repair really last? Or was it the residual corrosion that was probably partially shorting some of the traces. Or did the added heat of the removal and reinstall of the RAM chip have a more lasting healing effect? Anyway, as it is now seems fine for now but I will keep an eye on it.
Anybody care to comment on why apparently this RAM chip came back from the dead? Or was it really dead to start with?
Alex
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Re: WTB AMI/Mostek MK6220N RAM Chip
Once I took a flash photo (cameras used to have a flash that used special bulbs with magnesium filaments, and the camera spat out a picture on paper that appeared in about a minute) of a friend as he worked on a, probably 8080 or Z80, computer circuit that he had just got working. Immediately his circuit released a cloud of smoke before he could turn it off. After repairing the power supply the circuit still did not work and it was time to go home. The next morning the circuit was back to working. The cause was an open EPROM window and apparently the flash turned on elements that shorted the power supply. After a rest the chip recovered. I have seen other chips recover from abuse but replace them if possible. Yours may last another 20 years.
Here is an update on the removal of the RAM chip from the? main board.
The IC was unsoldered with soldapult pump and plenty of liquid flux. To clear some of the vias and since most pins where resting on the inner walls of the vias, had to first center them in the hole and then retry clearing it out of solder. On the top side of the board had to use solder wick to clear some excess solder holding some of the pins to the board. It took a while but eventually managed to gently pry the chip loose.
There was indeed still some corrosion left on and between 3 of the 4 traces that run under the IC, but very light not really much. Cleaned up traces with 91% IPA, and a Q-tip. The IC body itself seemed clean on the bottom and in between the pins, but just in case gave it a gentle brushdown with IPA as well. Also cleaned up the residual flux left on the board. Happned to have two 10-pin low-profile socket strips (these cost almost 50 cents/pin!) so trimmed then down to 8 pins each and mounted the RAM chip to align all the pins properly and then soldered the socket. Only soldered the pins that are actually in use which on this chip is only 8 out of 16. Just in case to make it easier if in the future I ever needed to remove the socket.
After powering up the calculator it worked 100%. It certainly must be due to residual heat from the desoldering/resoldering operation.
30 minutes later it still works. Completely removed power and let it sit for about 3 hours, test again: still working. Put the board back into the calculator case and reassembled it, put in the battery pack: still going.
It is now almost 20 hours after the repair and the calculator is still working 100%. Last night gave it a through workout to test all functions, and ran a short program. Everything worked.
Only question is, will this repair really last? Or was it the residual corrosion that was probably partially shorting some of the traces. Or did the added heat of the removal and reinstall of the RAM chip have a more lasting healing effect? Anyway, as it is now seems fine for now but I will keep an eye on it.
Anybody care to comment on why apparently this RAM chip came back from the dead? Or was it really dead to start with?
Alex
|
Re: WTB AMI/Mostek MK6220N RAM Chip
Here is an update on the removal of the RAM chip from the main board.
The IC was unsoldered with soldapult pump and plenty of liquid flux. To clear some of the vias and since most pins where resting on the inner walls of the vias, had to first center them in the hole and then retry clearing it out of solder. On the top side of the board had to use solder wick to clear some excess solder holding some of the pins to the board. It took a while but eventually managed to gently pry the chip loose.
There was indeed still some corrosion left on and between 3 of the 4 traces that run under the IC, but very light not really much. Cleaned up traces with 91% IPA, and a Q-tip. The IC body itself seemed clean on the bottom and in between the pins, but just in case gave it a gentle brushdown with IPA as well. Also cleaned up the residual flux left on the board. Happned to have two 10-pin low-profile socket strips (these cost almost 50 cents/pin!) so trimmed then down to 8 pins each and mounted the RAM chip to align all the pins properly and then soldered the socket. Only soldered the pins that are actually in use which on this chip is only 8 out of 16. Just in case to make it easier if in the future I ever needed to remove the socket.
After powering up the calculator it worked 100%. It certainly must be due to residual heat from the desoldering/resoldering operation.
30 minutes later it still works. Completely removed power and let it sit for about 3 hours, test again: still working. Put the board back into the calculator case and reassembled it, put in the battery pack: still going.
It is now almost 20 hours after the repair and the calculator is still working 100%. Last night gave it a through workout to test all functions, and ran a short program. Everything worked.
Only question is, will this repair really last? Or was it the residual corrosion that was probably partially shorting some of the traces. Or did the added heat of the removal and reinstall of the RAM chip have a more lasting healing effect? Anyway, as it is now seems fine for now but I will keep an eye on it.
Anybody care to comment on why apparently this RAM chip came back from the dead? Or was it really dead to start with?
Alex
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What is it doing wrong? 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.
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On May 22, 2019, at 19:20, Brian < brianclarke01@...> wrote: Hello folks,
I have an HP 5345A whose display is faulty. When I look in the service manual, I am enjoined to replace the whole front panel.
Can you help?
73 de Brian, VK2GCE
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Hello folks,
I have an HP 5345A whose display is faulty. When I look in the service manual, I am enjoined to replace the whole front panel.
Can you help?
73 de Brian, VK2GCE
|
Re: WTB AMI/Mostek MK6220N RAM Chip, black foam storage
I have seen similar issues with some chips
stored in black foam, mostly on some chips I have collected, ?at a garage
sale.
?
I had one ¡°little drawer¡± cabinet
with a fair number of 74xxx type chips from the late 70¡¯s to early 80¡¯s.
It had clearly been in the garage, the sale was in, for a few decades.
?
Most of the black foam that was in larger
sheets did not cause damage and the chips were in good condition. But some with
a small piece of? black foam between the pins rusted the legs off the
chips, some so much that all the legs fell off when picked up.
?
I would say that the foam that did the
damage looked like it was from chips that had been in sold as singles or doubles
that were in the ?cardboard package with the clear plastic top vacuum
packed on top.
?
Like one would see hanging in Radio Shack,
or the electronics stores of days gone by, ?with the foam just the size of
the chip.
?
The ¡°foam¡± felt dry and crumbled
when touched.
?
I think that foam retained condensate or moisture
over time ?in some way, resulting in rust.
?
I would be interested if there is some
scoop on black conductive foam I should know about
?
Because I never know when I might need a
chip to fix a piece of HP gear
?
John
?
?
?
?
?
?
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From: [email protected] [mailto:[email protected]] On Behalf Of peter bunge
Sent: Wednesday, May 22, 2019 6:17
AM
To: [email protected]
Subject: Re:
[HP-Agilent-Keysight-equipment] WTB AMI/Mostek MK6220N RAM Chip
?
There is another issue with older chips in storage. That black anti
static foam that was used will dissolve the pins off the chips.
I have a sheet with over a dozen chips in various stages of
deterioration with weakened and brittle pins, discolored pins (even gold
plated), and pins that look rusty. The black foam apparently has a chemical
reaction to the metal. Some may be purple plague by the color.
Does anyone have a solution to cleaning the black goo of chips, some
rare chips are worth saving if not too bad.
And, with apologies for OT, can anyone identify this chip? It is 18 pin
marked C80008 (not to be confused with the 8008 CPU which is also 18 pin).
?
Hi George,
I guess you are referring to the "Gold¨Caluminium intermetallic"
problem.
Some notes from around 1987 I also found suggest this might not only been a
problem of the past, but may have affected more modern devices of the time as
well.
Purple plague: Eliminated or just forgotten?
Abstract
The reappearance of ¡®purple plague¡¯ as a reliability and failure
risk in current IC devices has led to renewed
interest in the precise failure mechanisms and eventual failure mode. These are
outlined and illustrated with examples of recent failures in plastic
encapsulated integrated circuits, hermetically sealed integrated circuits and
hybrids. The reasons for the reappearance of this type of failure are
discussed, and it is shown that the problem may be expected to increase in
future generation devices.
I do not have further access to the article, nor did I intend to read the whole
thing, but I guess by now the problem has been solved (?).
=============
On Tue, May 21, 2019 at 09:43 AM, george edmonds
wrote:
>
> Hi Alex
> Back in the dim and distant past there was a problem with faulty epoxy
that
> was used to encapsulate chips, the problem was known as the purple
plague.?
> Regards
> George G6HIG?
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Re: Looking for memory dump of EPROM of HP 8660D CPU-Board
Thank you for the hints.
The option H32 seems to be special operatinng functions or something like that.
I try to control the HP8660D via HPIB-Connection and some commands of the operating manual will be rejected and gave an error message.
Eg. the command to set the sweep speed.
In the meantime i began to disassemle the code for the integrated microprocessor MC6802.
I hope to find all the possible commands for remote controlling.
The repair/adjustment of the unlocked PLL was the other path to bring the HP8660D back to live...
It sounds relative easy.
Maybe someone has a copy of the EPROM of the CPU card. I am very interested.? :-)
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Mike
What is the CW key I am selling in the first JPEG photo?
Love to have that greyl ine clock, but too far....:
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Brian