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Re: HP8565 hacking/mods
one problem i find is that the market for stuff like this is soo small that
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it isnt worth my time. i cant afford to spend alot of time on things that have very little return at oner time i had enough money to play for long periods of time that isnt the case any longer im not as fotunate as john miles. ----- Original Message -----
From: John Miles To: hp_agilent_equipment@... Sent: Saturday, November 17, 2007 3:16 PM Subject: RE: [hp_agilent_equipment] HP8565 hacking/mods > Hi John, > Yes I have seen that unit - I was pondering something more > sophisticated. Along the lines of 100MSa/s to FPGA to digitize x,y or > if and an embedded web-server to get the data out. Keep in mind that there's no benefit to digitizing post-detected trace signals (x and y) at rates beyond the bandwidth of the widest video filter, typically a few MHz at most. And if you digitize the final IF, the bandwidth may still be limited to a few MHz by other filters in the SA's signal chain. If you are that ambitious, I think the best approach -- meaning, the one that would benefit others the most, and require you to do the least original engineering work -- would be to launch a project using the USRP or other GNU Radio peripherals as a general-purpose spectrum analyzer back end. Keep it simple at first or you'll never get anywhere! Trust me on that... > I figure I might > have enough space on that board and use the control inputs for other > purposes such as selected storage mode or other function since they > wouldn't be controlling the tube any more. Still early ponderances - > I only just got the SA and need to play with it a bit more!! I've > decided its time to move into the exciting world of RF and high speed > digital - spent enough of time on slow - medium speed digital and > software - besides - that's what I do at work. It's definitely a good idea to spend time coming to grips with the limitations of what you have. The obvious specification deficiencies aren't always the ones that will end up limiting your measurements. > I was interested in your hybrid 2GHz vco and possible use as a yig > stabilizer. Heh... that will teach you all you (n)ever wanted to know about noise and stability. Building a clean YIG synthesizer is a challenging project. I still haven't managed to do as well as the old HP designs, even with much-newer opamps and other parts... which is one reason I chickened out when I realized I was faced with that sort of problem in my 8566 'redesign' project. It will have to wait until I can devote a lot more time to it. > I just realised that we looked at using your pc sound system where I > work. We're now moving from SGIs into pcs and may be looking at it > again. :-) Oh, you mean the sound system I'm supposed to be working on right now. Oh, yeah, THAT. :) -- john, KE5FX |
Re: HP8565 hacking/mods
John Miles
Hi John,Keep in mind that there's no benefit to digitizing post-detected trace signals (x and y) at rates beyond the bandwidth of the widest video filter, typically a few MHz at most. And if you digitize the final IF, the bandwidth may still be limited to a few MHz by other filters in the SA's signal chain. If you are that ambitious, I think the best approach -- meaning, the one that would benefit others the most, and require you to do the least original engineering work -- would be to launch a project using the USRP or other GNU Radio peripherals as a general-purpose spectrum analyzer back end. Keep it simple at first or you'll never get anywhere! Trust me on that... I figure I mightIt's definitely a good idea to spend time coming to grips with the limitations of what you have. The obvious specification deficiencies aren't always the ones that will end up limiting your measurements. I was interested in your hybrid 2GHz vco and possible use as a yigHeh... that will teach you all you (n)ever wanted to know about noise and stability. Building a clean YIG synthesizer is a challenging project. I still haven't managed to do as well as the old HP designs, even with much-newer opamps and other parts... which is one reason I chickened out when I realized I was faced with that sort of problem in my 8566 'redesign' project. It will have to wait until I can devote a lot more time to it. I just realised that we looked at using your pc sound system where IOh, you mean the sound system I'm supposed to be working on right now. Oh, yeah, THAT. :) -- john, KE5FX |
Re: Hp-8443A Tracking Generator Problems
lothar baier
you might want to try ebay, another way is to find the connectors or strip them out of a old unit and then make a PCB board for it, all you need is the spacing for the board.
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If you dont have any way of etching boards and dont want a boarshop doing it you can just get a strip of 2 sided FR4 about 1" wide, layout your contacts with a ruler and then use a dremel tool or a sharp knive to cut insulation channels in between the contacts, use a piece of ribbon cable to connect this contact to the female part (the green connector) and there you made yourself a extender board ! most of the RF stuff is routed trough coax so the contacts only carry DC and control signals David C. Hallam" <dhallam@...> wrote: I guess I have to amend my posting and apologize to HP. I misread the drawing for the SMB connector and in fact these connectors are SMB. They are not "goofy". Also, I think I have located a 500 MHz plug-in for my 5245L counter. Now, if I could just find the extender cards to service the modules, I would be on my way to relatively painless trouble shooting of the 8443A. Repairs may be another matter. David KC2JD/4 -----Original Message-----
From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]On Behalf Of David C. Hallam Sent: Friday, November 16, 2007 6:19 PM To: hp_agilent_equipment@... Subject: RE: [hp_agilent_equipment] Hp-8443A Tracking Generator Problems I did call them GOOFY because that is what they are. They are goofy because I think the only place in the whole world they were used was the jacks and plugs for the cables of the connections between modules of the 8443A. They are not SMA, SMB, or SMC. I have looked at drawing of each of these types are the are not same as what HP used. I have no idea what they are or where to obtain them. I would certainly appreciate it if anyone could identify them along with a source of supply. As far as I am concerned their official description is "unobtainiun". David KC2JD/4 -----Original Message----- From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]On Behalf Of David Wise Sent: Friday, November 16, 2007 5:03 PM To: hp_agilent_equipment@... Subject: RE: [hp_agilent_equipment] Hp-8443A Tracking Generator Problems I didn't call them goofy, David Hallam (the OP) did. You and I are referring to what's more commonly called "Hybrid-D" connectors. (From context, I judge that David Hallam is thinking of the SMB (SMC?) plugs on the inter-assembly cables inside the instrument. The hybrid-D of interest in this thread actually has no standard D contacts at all, it's all coaxes. Which by the way are called "Size 8". Not to inundate you with 8's, but the connector pin layout is called "8W8", which predictably means 8 contacts 8 of which are coax. Regards, Dave Wise -----Original Message----- --------------------------------- Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how. |
Re: Hp-8443A Tracking Generator Problems
lothar baier
the coax contacts are made by ITT Cannon as well as some other companies, you can buy them from mouser, digi key or pasternack, the only problem is that they are crimped on the outside so you need a crimping tool.
pasternack also sells cables with the contacts already crimped on but they run about $20ea, howewer if you consider the cost of a contact @ $3-4ea, the time you spend stripping the coax and about $50-100 for the crimping tool you might want to consider buying the cables ready made J Forster <jfor@...> wrote: It turns out they are 50 Ohm SMBs. Interestingly SMBs have become a lot more common (and cheaper) recently because of GPS and wireless networking and extension cables and adapters are now readily available on eBay. Best, -John w6sfh wrote: Gentlemen, David C. Hallam wrote:John, --------------------------------- Get easy, one-click access to your favorites. Make Yahoo! your homepage. |
Re: Hp-8443A Tracking Generator Problems
David C. Hallam
I guess I have to amend my posting and apologize to HP. I misread the
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drawing for the SMB connector and in fact these connectors are SMB. They are not "goofy". Also, I think I have located a 500 MHz plug-in for my 5245L counter. Now, if I could just find the extender cards to service the modules, I would be on my way to relatively painless trouble shooting of the 8443A. Repairs may be another matter. David KC2JD/4 -----Original Message-----
From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]On Behalf Of David C. Hallam Sent: Friday, November 16, 2007 6:19 PM To: hp_agilent_equipment@... Subject: RE: [hp_agilent_equipment] Hp-8443A Tracking Generator Problems I did call them GOOFY because that is what they are. They are goofy because I think the only place in the whole world they were used was the jacks and plugs for the cables of the connections between modules of the 8443A. They are not SMA, SMB, or SMC. I have looked at drawing of each of these types are the are not same as what HP used. I have no idea what they are or where to obtain them. I would certainly appreciate it if anyone could identify them along with a source of supply. As far as I am concerned their official description is "unobtainiun". David KC2JD/4 -----Original Message----- From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]On Behalf Of David Wise Sent: Friday, November 16, 2007 5:03 PM To: hp_agilent_equipment@... Subject: RE: [hp_agilent_equipment] Hp-8443A Tracking Generator Problems I didn't call them goofy, David Hallam (the OP) did. You and I are referring to what's more commonly called "Hybrid-D" connectors. (From context, I judge that David Hallam is thinking of the SMB (SMC?) plugs on the inter-assembly cables inside the instrument. The hybrid-D of interest in this thread actually has no standard D contacts at all, it's all coaxes. Which by the way are called "Size 8". Not to inundate you with 8's, but the connector pin layout is called "8W8", which predictably means 8 contacts 8 of which are coax. Regards, Dave Wise > -----Original Message----- > From: hp_agilent_equipment@... > [mailto:hp_agilent_equipment@...]On Behalf Of J Forster > Sent: Friday, November 16, 2007 2:02 PM > To: hp_agilent_equipment@... > Subject: Re: [hp_agilent_equipment] Hp-8443A Tracking > Generator Problems > > > Sealectro is a brand. They made SMA, SMB, SMC, and a number > of other miniature > coax connectors. They ALSO made a number of proprietary types > in addition to the > standards. > > As to 'goofy', do you mean the D connectors w/ the mix of > coax and ordinary > pins? > > -John > > > > David Wise wrote: > > > They did call them by an obsolete name, "selectro" (or was > it "sealectro"?). > > > > > > > Yahoo! Groups Links > > > > |
Re: Hp-8443A Tracking Generator Problems
J Forster
It turns out they are 50 Ohm SMBs.
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Interestingly SMBs have become a lot more common (and cheaper) recently because of GPS and wireless networking and extension cables and adapters are now readily available on eBay. Best, -John w6sfh wrote: Gentlemen, David C. Hallam wrote:John, |
Re: Hp-8443A Tracking Generator Problems
w6sfh wrote:
I've already said this but nobody wants to believe it Bob. But great to get it confirmed from the source. As for the interconnect cable from the tracking generator to the spectrum analyzer, it's not necessary to have the connector shell. If you can find the appropriate coax connector inserts (sorry, but I don't know the part numbers), they can be used without the shell,The 8W8 shells are readily available, from Mouser, among others. Quite cheaply in fact. $3 or $4 from memory. The coax inserts are also available as are metal shrouds and the slide locks 73 Dan ac6ao |
Re: Hp-8443A Tracking Generator Problems
w6sfh
Gentlemen,
I have two HP 8443 tracking generators, one is an "A" model with the counter and one is a "B" model without the counter. Both use SMB connectors on the coaxes that interconnect the individual PC board assemblies. SMC connectors are used on the step attenuators and the blocking capacitor assembly on the output connector. Note that one end of each RF cable is permanently attached to the cover of the PC board assembly. I worked for Hewlett-Packard at the factory where the HP 8443's were manufactured and I don't recall ever seeing anything but SMB and SMC connectors used for this type of application in those days. As for the interconnect cable from the tracking generator to the spectrum analyzer, it's not necessary to have the connector shell. If you can find the appropriate coax connector inserts (sorry, but I don't know the part numbers), they can be used without the shell, as there is enough friction to hold them in place when inserted into the connectors on the tracking generator and spectrum analyzer rear panels. The positions on each end correspond one-for-one. Of course you'll have to be careful not to dislodge the connectors, but for bench top applications this should not be a problem. Also, the system may not pass the original specifications for radiated emissions and susceptability without the original interconnect cable, but again this may not be a problem for most applications. Regards, Bob Dildine --- In hp_agilent_equipment@..., "Dave Brown" <tractorb@...> wrote: connector plus a short length of coax from surplus equipment-depending onwhat test lead(s?) you want to make up. Microdots were used in 76 and 78source Forsterof GeneratorSent: Friday, November 16, 2007 6:45 PM andProblems areouter thegoofy of8443A. theythese anyoneare or could |
Re: HP8565 hacking/mods
lothar baier
ok , you got me confused here, the 8565 does not have a storage pcb since it uses a storage CRT , as far as connecting a digitizer that should be fairly easy, as far as i remember the 8565 has a interface connector to connect a storage normalizer (8750) on the back panel, this connector gives you acess to all the signals you need for this task.
However if you put in the time and effort to go for digital storage why dont you ponder the idea of discarding the CRT at all and replace it with a LCD panel, there is a bunch of embedded controllers that offer LCD/TFT interface build in, all you need is a microcontroller, A/D converter and a Surplus TFT panel and youre ready to go swingbyte <swingbyte@...> wrote: Hi fellow hp'ers, I'm the new owner of a HP8565 SA and think its pretty good. However, the hacker in me is already pondering modding it. In particular, I have been thinking of replacing the storage pcb with a new one, only operating the tube in conventional mode and using the rest of the space to add a digitiser/playback system. Has anyone else attempted something similar? Although digital systems and ADCs are now fast enough to do this - I chose the 8565 because it YIG RF systems still seem current state of art - and I could always digitise the rear outputs with something to avoid having to use the long persistence. I was prompted to write this after reading John Mills email about trying to increase the stability of his 8566 YIG and stated thinking maybe the 8565 could benefit from this? ( by the way - great web site you have!) The 8565 was at the price I could afford, I would have gone for an 8569 and would LOVE an 8566 - but here in Australia they're expensive - even through ebay - the shipping cost kills any bargains! But this is a hobby and I like hacking and modding. Another thought was to route the if signal to a DSO and FFT for greater resolution - would the 8565 LO be stable enough? Thanks for any thoughts Tim ( no call sign yet) --------------------------------- Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how. |
Re: Can 8568 be used without display unit?
lothar baier
There are several guys on ebay selling 8566/68 parts every now and then (playerservices for example) you might be able to find a interface card fairly cheap, also try best offers on fastscrap's items, altough his buy it now prices are unrealistic he sometimes accepts very low best offers, i wouldnt scrap the unit just for a missing card !
pierre288 <pierre288@...> wrote: John and Lothar, Thanks very much for your comments...you convinced me to forget interconnecting the 8568b/141t...not worthed. The long story is that I bought the 8568B without 85662A on ebay, and discovered the unit was missing the interface card...enough to stop me seeking for a display unit until I resolve my problem (finding an interface card seems hopeless...). Meanwhile, I bought a 141T display (alone), then gradually found missing modules (8552/8553/8555) which I succeeded fixing. Not having the energy (and money) to reinvest in an other 8568, then 85662, I'm rather closer to unload the 8568 I initially got...sniff...and never be able to see what "high stability" looks like...hihi 73 and best regards pierre...ve2ky --- In hp_agilent_equipment@..., lothar baier <microwaveengineer1968@...> wrote: actually has the processor in the display. hmmm why would anyone go through the trouble trying to build a85662A USB emulator ? with 85662A available under $500 this would be a dead end projectmicroprocessor is in the RF section, but in practice I agree with Lothar that it would be a hugewaste of time.(such as marker amplitudes) back from the display section. And you would getnone of the 8568B's alphanumerics or graticule graphics, because those aregenerated by the vector hardware in the 85662A. Even if you succeeded in getting amuch-cruder one, and the system will have all of the limitations of the 141T and noneof the advantages of the 8568B except, I guess, its stability.emulate the 85662A via USB, but that adapter is not going to be cheap or simple.8568...
--------------------------------- Be a better pen pal. Text or chat with friends inside Yahoo! Mail. See how. |
Re: HP8565 hacking/mods
swingbyte
Hi John,
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Yes I have seen that unit - I was pondering something more sophisticated. Along the lines of 100MSa/s to FPGA to digitize x,y or if and an embedded web-server to get the data out. I figure I might have enough space on that board and use the control inputs for other purposes such as selected storage mode or other function since they wouldn't be controlling the tube any more. Still early ponderances - I only just got the SA and need to play with it a bit more!! I've decided its time to move into the exciting world of RF and high speed digital - spent enough of time on slow - medium speed digital and software - besides - that's what I do at work. I was interested in your hybrid 2GHz vco and possible use as a yig stabilizer. I just realised that we looked at using your pc sound system where I work. We're now moving from SGIs into pcs and may be looking at it again. :-) Tim John Miles wrote: I was promptedThanks! You should probably check out the Nov-Dec '07 QEX article by Roland Another thought was to route the if signal to a DSO and FFT for greaterPossibly. I'm not familiar with this particular unit but if you do this, |
Re: HP8565 hacking/mods
John Miles
I was promptedThanks! You should probably check out the Nov-Dec '07 QEX article by Roland Cordesses: The 8565 is similar enough to the 141T (basically a newer, more compact version) that the same techniques should be usable with it. Another thought was to route the if signal to a DSO and FFT for greaterPossibly. I'm not familiar with this particular unit but if you do this, you will quickly learn whether or not it's stable enough. :) Then the real hacking can begin. -- john, KE5FX |
HP8565 hacking/mods
swingbyte
Hi fellow hp'ers,
I'm the new owner of a HP8565 SA and think its pretty good. However, the hacker in me is already pondering modding it. In particular, I have been thinking of replacing the storage pcb with a new one, only operating the tube in conventional mode and using the rest of the space to add a digitiser/playback system. Has anyone else attempted something similar? Although digital systems and ADCs are now fast enough to do this - I chose the 8565 because it YIG RF systems still seem current state of art - and I could always digitise the rear outputs with something to avoid having to use the long persistence. I was prompted to write this after reading John Mills email about trying to increase the stability of his 8566 YIG and stated thinking maybe the 8565 could benefit from this? ( by the way - great web site you have!) The 8565 was at the price I could afford, I would have gone for an 8569 and would LOVE an 8566 - but here in Australia they're expensive - even through ebay - the shipping cost kills any bargains! But this is a hobby and I like hacking and modding. Another thought was to route the if signal to a DSO and FFT for greater resolution - would the 8565 LO be stable enough? Thanks for any thoughts Tim ( no call sign yet) |
Re: Can 8568 be used without display unit?
John and Lothar,
Thanks very much for your comments...you convinced me to forget interconnecting the 8568b/141t...not worthed. The long story is that I bought the 8568B without 85662A on ebay, and discovered the unit was missing the interface card...enough to stop me seeking for a display unit until I resolve my problem (finding an interface card seems hopeless...). Meanwhile, I bought a 141T display (alone), then gradually found missing modules (8552/8553/8555) which I succeeded fixing. Not having the energy (and money) to reinvest in an other 8568, then 85662, I'm rather closer to unload the 8568 I initially got...sniff...and never be able to see what "high stability" looks like...hihi 73 and best regards pierre...ve2ky --- In hp_agilent_equipment@..., lothar baier <microwaveengineer1968@...> wrote: actually has the processor in the display. hmmm why would anyone go through the trouble trying to build a85662A USB emulator ? with 85662A available under $500 this would be a dead end projectmicroprocessor is in the RF section, but in practice I agree with Lothar that it would be a hugewaste of time.(such as marker amplitudes) back from the display section. And you would getnone of the 8568B's alphanumerics or graticule graphics, because those aregenerated by the vector hardware in the 85662A. Even if you succeeded in getting amuch-cruder one, and the system will have all of the limitations of the 141T and noneof the advantages of the 8568B except, I guess, its stability.emulate the 85662A via USB, but that adapter is not going to be cheap or simple.8568...
|
Re: Hp-8443A Tracking Generator Problems
Dave Brown
David-
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If they ARE microdots, then it may be an option to recover a connector plus a short length of coax from surplus equipment-depending on what test lead(s?) you want to make up. Microdots were used in 76 and 78 series Lenkurt (analog microwave radio) gear-for example. But pictures are essential to know exactly what you need. DaveB, NZ ----- Original Message -----
From: "J Forster" <jfor@...> To: <hp_agilent_equipment@...> Sent: Saturday, November 17, 2007 4:32 PM Subject: Re: [hp_agilent_equipment] Hp-8443A Tracking Generator Problems jfor@... |
Re: Hp-8443A Tracking Generator Problems
J Forster
jfor@...
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As to a source, there are a number of distributers, but they will likely be expensive. -J David C. Hallam wrote: John, |
Re: Hp-8443A Tracking Generator Problems
David C. Hallam
John,
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They are gold plated and have Teflon insulation. I'll send a couple of pictures tomorrow. I hope you can identify them and give a source of supply. What is your email address? David -----Original Message-----
From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...]On Behalf Of J Forster Sent: Friday, November 16, 2007 6:45 PM To: hp_agilent_equipment@... Subject: Re: [hp_agilent_equipment] Hp-8443A Tracking Generator Problems They are very likely Sealectro or MicroDot. If you email me a (small ) pic of both M and F, off list, I'll see if I can ID them. If they are gold plated with Teflon insulation between center and outer conductors, Sealectro is the most likely choice. -John David C. Hallam wrote: > I did call them GOOFY because that is what they are. They are goofy because > I think the only place in the whole world they were used was the jacks and > plugs for the cables of the connections between modules of the 8443A. They > are not SMA, SMB, or SMC. I have looked at drawing of each of these types > are the are not same as what HP used. I have no idea what they are or > where to obtain them. I would certainly appreciate it if anyone could > identify them along with a source of supply. As far as I am concerned their > official description is "unobtainiun". > > David > KC2JD/4 |
Re: Stellex YIGs
lothar baier
Im a bit on the bad side with hittite right now, when i was working at the big M i didnt have any problems getting samples from them but now its not as easy , they want me to buy the samples but then they have a min order of 10ea which really is overkill financially !
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The reason why you cant get past 10GHz is that as far as i know those YIGs use bipolar transistors and not GaAS, the phase noise performance seem to support this theory, getting anything out of a bipolar transistor past 10GHz is a tough job, i spend countless days and month testing simulating and building prototypes trying to get a 12GHz DRO going (to be used as one half of a push push design for 24GHz), there are a few good devices from infineon and a fairly new one from NXP that produce results but back when those endwave parts were conceived state of the art was about 10GHz ! Im really only interested in 8GHz which the device should do, im using a passive doubler to go to 16GHz and then a MIMIX Doubler to go to 32GHz, why a passive doubler for the first stage ? well the answer is simple, im getting about +14dBm from the YIG, active doublers usually take about -6 to 0dBm so i would have to kill almost 14dB, the conversion loss of the doubler is 12dB so im ending up with +2dBm, now run this signal trough a splitter, lose 6dB thats -4dBm , the active doubler i use produces +16dBm @ 0dBm input so im getting about +14dBm at the output which is perfect. John Miles <jmiles@...> wrote: I have tried running those YTOs past 10 GHz, and what happens is that they just stop oscillating beyond a certain point (about 10.3 GHz as I recall). If you bolt the oscillator to a good thermal sink and keep an eye on the temperature it will probably be safe enough... but whether it will still oscillate is another question. I'd be interested in hearing how things go with the sampling phase detector. Conversion loss at high harmonics, and the resulting need for lots of IF gain, can really eat your lunch with those. From what I've seen there is no longer much upside to using harmonic samplers over modern PFD chips. The best of the Analog Devices parts (ADF4108, about $7/ea.) will work at Fin=8 GHz and Fcomp=100 MHz. You can't run either of them at N=32,000 and expect miracles, obviously. Obligatory HP content: I spent a lot of time trying to clean up my 8566B's first LO synthesizer before I realized that the conversion loss of the YTO sampler was never going to let me do better than about -105 to -110 dBc/Hz. The low effective N factor rules out the ADF41xx series PLLs in that application, but I think I could have gotten into the -120 dBc/Hz range with a Hittite HMC363/HMC439 combination if my motivation hadn't run out. -- john, KE5FX -----Original Message----- --------------------------------- Never miss a thing. Make Yahoo your homepage. |
Re: Stellex YIGs
John Miles
I have tried running those YTOs past 10 GHz, and what happens is that they
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just stop oscillating beyond a certain point (about 10.3 GHz as I recall). If you bolt the oscillator to a good thermal sink and keep an eye on the temperature it will probably be safe enough... but whether it will still oscillate is another question. I'd be interested in hearing how things go with the sampling phase detector. Conversion loss at high harmonics, and the resulting need for lots of IF gain, can really eat your lunch with those. From what I've seen there is no longer much upside to using harmonic samplers over modern PFD chips. The best of the Analog Devices parts (ADF4108, about $7/ea.) will work at Fin=8 GHz and Fcomp=100 MHz. You can't run either of them at N=32,000 and expect miracles, obviously. Obligatory HP content: I spent a lot of time trying to clean up my 8566B's first LO synthesizer before I realized that the conversion loss of the YTO sampler was never going to let me do better than about -105 to -110 dBc/Hz. The low effective N factor rules out the ADF41xx series PLLs in that application, but I think I could have gotten into the -120 dBc/Hz range with a Hittite HMC363/HMC439 combination if my motivation hadn't run out. -- john, KE5FX -----Original Message----- |
Re: Stellex YIGs
lothar baier
thanks for the datasheet, unfortunatly it doesnt give a max current for the coil, the part i have says 8.5-9.25GHz it tunes to 8GHz @ 150mA however i dont know if this is acceptable for long term operation.
I know about the phasenoise performance for the synthesizers thats why im using a SPD rather than a PLL Chip along with a 100MHz low phasenoise reference. Endwave actually swallowed Stellex as far as i know, stellex used to be WJ components , then WJ became stellex and then stellex got taken over by endwave. John Miles <jmiles@...> wrote: They're equivalent to these Endwave parts, as far as I can tell: The YTOs themselves are nice parts, but the popular synthesizer boards that use them are noisy. The comparison frequency is relatively low (250 kHz), causing a 90-dB in-band PN penalty. With a higher Fcomp you can do quite a bit better. -- john, KE5FX Does anyone has a detailed datasheet of the stellex permanent magnet --------------------------------- Never miss a thing. Make Yahoo your homepage. |
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