Microwave power source.... from a Canadair - Page 1
Forum section: electronics / rf-microwave

author: Fiorenzo
author_rank: Regular Contributor
timestamp: September 29, 2019, 11:15:14 am
content: Hi dear,a friend of mine have found these 2 components that should be parts of a so called "microwave power source" .These are old parts that came off a canadair airplane.Do you know what are and if they could be of interest?See the attached photos.........

author: TheMG
author_rank: Frequent Contributor
timestamp: September 29, 2019, 11:40:07 pm
content: Part of a radio-altimeter system maybe?Any part number on the outside of these modules?

author: coppercone2
author_rank: Super Contributor
timestamp: September 30, 2019, 12:52:00 am
content: i think it would be a power supply for a doppler radarcheck the voltage levels to see if its using high power tubes (TWT)

author: MagicSmoker
author_rank: Super Contributor
timestamp: September 30, 2019, 09:48:52 am
content: It's definitely not a high power device so unlikely to be a Doppler radar or TWT supply. More than likely it is a IMPATT or Gunn diode based oscillator, though for what I'm not sure.

author: LaserSteve
author_rank: Super Contributor
timestamp: September 30, 2019, 02:33:59 pm
content: Looks like two SRD multiplier chains.Steve

author: Fiorenzo
author_rank: Regular Contributor
timestamp: September 30, 2019, 05:19:01 pm
content: Actually it has a big Cristal and the wiring looks like for high frequency

author: radiolistener
author_rank: Super Contributor
timestamp: September 30, 2019, 09:05:35 pm
content: I'm not sure about electronics, but the shielding is very good and will be very useful for ham radio amateurs to use it for RF circuits. For example RF low noise amplifiers, RF modules for SDR receivers, etc. I also want such cool shieldingCrystal also may be very useful. it looks like low phase noise oscillator. If so, then it also will be very useful for ham radio amateurs, for high dynamic range receivers, SDR, etc.

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 01, 2019, 04:49:24 am
content: Understood, but i am not an expert on radio equipment so I cannot figure out for what purpose they made those apparatuses and how they specifically works. For exemple the little one seem to have three different channel but not sure for what.The same the bigger one has obviously an oscillator plus 3 that are the same to each other

author: Melt-O-Tronic
author_rank: Frequent Contributor
timestamp: October 01, 2019, 06:03:40 am
content: What's the purpose of blacking out the part numbers? Those are probably the easiest clues to identify the units.

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 01, 2019, 06:55:08 pm
content: You are right but my friend is paranoic

author: radiolistener
author_rank: Super Contributor
timestamp: October 01, 2019, 07:32:17 pm
content: Quote from: Fiorenzo on October 01, 2019, 06:55:08 pmhe forgot to wipe out serial number, they can find the source by serial number

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 01, 2019, 08:30:18 pm
content: Ok fixed

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 01, 2019, 08:33:26 pm
content: So.... What to do with this stuff?I think they are quite old....

author: rfeecs
author_rank: Frequent Contributor
timestamp: October 01, 2019, 08:48:23 pm
content: Quote from: Fiorenzo on September 30, 2019, 05:19:01 pmThat is a DC-DC converter:https://www.amazon.com/Tecnetics-HCHR-015-228-Converter-28V-DC/dp/B00B05ZJBEThe flat module on the bottom labeled RF in / RF out is an RF amplifier. It takes 1.5A so probably a medium power amp with a few Watts output power.The boxes with multiple screws look like filters of some sort.The bottom PC board also has an amplifier chain, driven by maybe a diode comb generator or oscillator.The TO-5 can pictured is a crystal or crystal oscillator.

author: radiolistener
author_rank: Super Contributor
timestamp: October 01, 2019, 09:00:11 pm
content: Quote from: Fiorenzo on October 01, 2019, 08:30:18 pmtoo late... they already logged it.Now stay in place and wait for black helicopters

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 02, 2019, 04:18:23 am
content: I don't know why but is stuff that was found in a scrapyard

author: TheMG
author_rank: Frequent Contributor
timestamp: October 02, 2019, 04:23:16 am
content: Obsolete tech most likely. Especially on an aircraft where weight really matters, they could have very well upgraded to a newer system that does the same thing but is 1/4 of the size and weight. Could also be defective parts that were not worth fixing. Any number of reasons.

author: coppercone2
author_rank: Super Contributor
timestamp: October 03, 2019, 06:21:04 am
content: Quote from: MagicSmoker on September 30, 2019, 09:48:52 amyou are right, I looked at the pictures carefully and I don't see a potted kV transformer anywhere, They usually have a box thats coated in a thick layer of rubber

author: coppercone2
author_rank: Super Contributor
timestamp: October 03, 2019, 06:24:18 am
content: I don't know if you ever bought this stuff before, but it does make you a bit paranoid.It is export controlled and you get all sorts of stickers on it. One box I got looks like it can work in a CIA version of that bar from 'office space' where you need to wear the pins on your shirt. Like polka dots. Pretty sure it had a 'secret' sticker on it LOL before the goo-gone came out.How many people are really that confident that if you start buying export controlled electronic warfare equipment removed from a defense lab you won't get problems? The stickers only tell you 'electronic warfare' 'secret' and its made by the same company that designs stuff to blow up communism... I would even consider fear of that.. reasonable.. if a teenager bought that thing his parents would probably panicsure a expert knows you can buy a weird looking tile from analog.com that does most of the same stuff (so long you know how to do every other thing they did in that equipment to actually make it equipment, not a datasheet with nice specs and a diagram), but the postal inspector might think you are arming north korea LOLas for how to turn it on, you need to reverse engineer some of the circuits . find a power rail and then find something connected to it thats identifiable and then determine what it should be biased at to identify a plausible rail voltage. lots of work. likely a gigantic waste of time, so desolder parts from it and try making a 'simple' RF circuit (like that exists)there might be some nice functional RF transistors there that you can try to wind coils for to make simple oscillators, since it goes on an airplane its probably not gonna be useful for anything other then airplanes (for instance, on airplanes they use 400Hz power alot of the time, which just does not make sense for terrestrial use). that whole circuit was probably reduced to be functional for only what it was designed to do in the interests of weight and reliability. And the spec might not be impressive for test equipment standards, since its meant to do something within the limited resources of an airplane.. no one thought some genius is gonna find that and turn it into something nice (i.e. test equipment is designed with scientists in mind that do creative things, but this means more buttons, modes, more failure modes, etc).I would only save wideband amplifiers, filters or reference things that store in your lab nicely

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 03, 2019, 06:59:26 am
content: First of all I thank you and all the other guys.These pieces of equipment were found from my friend, he works in scrapyard.He worried to be doing something illegal possessing them but he was curious about what are... so he asked me but I am not an expert.Actually at this point I would be keen to understand if I can recover some of the components to re-use them in other applications. Also it would be interesting understanding what quartz is that and for what frequency it is set.

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 03, 2019, 07:08:53 am
content: Thank you for the insight, i thought that it was the quartz because on the lable placed on the enclosure it is written open to remove quartz.Quote from: rfeecs on October 01, 2019, 08:48:23 pm

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 03, 2019, 07:30:56 am
content: Actually I watched better to the circuit. Obviously all the components around the tecnetics dc converter has the purpose to be a power supply source for the "rf" can that is under it. But i still don't understand why its written that the "dc converter circuit" should has a quartz some where... Se the attached photo:Quote from: Fiorenzo on October 03, 2019, 07:08:53 am

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 03, 2019, 07:52:53 am
content: Also.... I don't understand the purpose of this metal block where the rf cable enters. There are also 9 screws that seem to be adjustable in heights because those are in different heights

author: PA0PBZ
author_rank: Super Contributor
timestamp: October 03, 2019, 09:31:47 am
content: Quote from: Fiorenzo on October 03, 2019, 07:52:53 amTunable/adjustable filters

author: radiolistener
author_rank: Super Contributor
timestamp: October 03, 2019, 10:41:18 am
content: Quote from: Fiorenzo on October 03, 2019, 07:52:53 amlooks like cavity filters.

author: radiolistener
author_rank: Super Contributor
timestamp: October 03, 2019, 10:56:10 am
content: Quote from: Fiorenzo on October 03, 2019, 07:30:56 amit looks like crystal is placed in the gray shield box with RF connector (see under power supply shield box).

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 03, 2019, 01:41:42 pm
content: Searching on the web with all the serial number was unusefull untill i typed: varian 88236This code seem to be added manually near the other parts number.The research gives results about varian magnetrons:https://www.google.it/search?q=varian+88236&client=ms-opera-mobile&channel=new&espv=1&prmd=imsvn&sxsrf=ACYBGNQ05vVS0buHn8mmywYNVsBryOPghw:1570109440527&source=lnms&tbm=isch&sa=X&ved=2ahUKEwil39e7mYDlAhWIYlAKHYjvD_EQ_AUoAXoECGcQAQ&biw=412&bih=660&dpr=2.63

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 03, 2019, 03:07:12 pm
content: So, i disassembled it a little more:The can is completely sealed, i tried gently to open it with a 32 metric ton press (i am not kidding), no way to open it.In sum: if that can is an rf amplifier it shouldn't have a cristal... But not sure what it have inside, you know better...Is possible that the dc dc converter from tecnetics has a cristal inside?

author: radiolistener
author_rank: Super Contributor
timestamp: October 03, 2019, 04:29:24 pm
content: Previously I thought this is something like VCXO, with control voltage input and RF output. But now I'm not sure, since input is marked as RF input...May be this is klystron?

author: PA0PBZ
author_rank: Super Contributor
timestamp: October 03, 2019, 06:39:58 pm
content: So here is my take:Power supplywith at least + and - 15V output, the DC converter is probably used to create the -15VFrequency generatorwith 3 identical crystal oscillators, the crystals (C) are marked with the frequency.Not sure if they run in parallel and are mixed or they are switchable, the details are hidden below the oscillators.The filter is filtering the output signalRF Amplifierwith +-15V supplyDetectorwith feedback to the generator (the black(?) wire) to get a constant outputRF outputon the side, is that a waveguide?If it is aircraft it is probably powered by 28V

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 03, 2019, 09:11:14 pm
content: Interesting, and what do you think the purpose of the other smaller circuit box with that 3 oscillator plus filter?

author: radiolistener
author_rank: Super Contributor
timestamp: October 03, 2019, 09:46:56 pm
content: Quote from: Fiorenzo on October 03, 2019, 09:11:14 pmSince it has exactly the same modules and filter, this is also osclillator source, but with no power amplifier. Maybe frequency is a little higher, because cavity filter is a little smaller.

author: Fiorenzo
author_rank: Regular Contributor
timestamp: October 04, 2019, 02:42:03 pm
content: Thank you, so at the end all this staff to do what?

author: PA0PBZ
author_rank: Super Contributor
timestamp: October 04, 2019, 06:15:40 pm
content: Quote from: Fiorenzo on October 04, 2019, 02:42:03 pmSo, what else do you want to know? Can you use it for something as it is? No, there's nothing you could use it for. Do you want to know what it can do? take it apart further (specially what's under the oscillators, make some pictures and we all can have a guess. I asked you if the output is a waveguide but you didn't answer that yet. If it is measure the width and height of the output window and you will know the approx frequency it generates. If everything else fails take it apart and maybe use the parts for another project. Or send it to me and I'll try to power it up so I can tell you exactly what it does

author: LaserSteve
author_rank: Super Contributor
timestamp: October 08, 2019, 02:30:25 pm
content: The nine screws will likely tune a stepped ridge waveguide filter for the step recovery diode frequency multiplier. One is the SRD input matching. Seven are the tuning of the ridged waveguide filter, and one is the output matching.Your likely looking at a x-band or c-band Doppler navigation master oscillator or Radar coherent local oscillator. (COLO)Google "Frequency West Microwave Brick SRD Ham Radio" and you might learn something, for what your looking at is a similar system.Now that I can see a waveguide in the one picture, it looks like WR90, so X-Band around 9 Ghz.So those are SRD multipliers driven by crystal master oscillators.Steve