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Test Equipment / Anritsu MS2670A
« Last post by NavyBOFH on Today at 09:15:24 AM »
I was wondering if anyone on here has come across anything for these before? I have two that I picked up, both working and one with a recently expired calibration sticker, and one that looks fine but seems to have a blown front end and possibly tracking generator issues as well.

I found a single mentioning on here that it was a military custom model, but I have not the slightest clue what the next closest model would be to look up for a service manual... or if anyone here might have a service manual for it?

I would love to get the second unit fixed since the first one is being put to work pretty heavily already. Any help would be appreciated!
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Beginners / Re: Function generator question
« Last post by BreakingOhmsLaw on Today at 09:14:52 AM »
 - What are you using to measure this signal? An oscilloscope probe, or one of those BNC/Banana-plug adapters? Let's see your measurement setup.
 - Does the FG085 Square look noisy too, when you don't attach a load to it? Try a BNC lead straight to the scope.
 - I see your function generator board runs on a wall socket power supply. Your supply might be inadequate, check the rating.
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Please don't hijack this thread with hacking talk.
The thread is big enough as it is.
By all means take it to another thread if you want.
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Repair / Re: Repair of Tektronix FG502 11 MHz Function Generator
« Last post by xrunner on Today at 09:10:06 AM »
Where do you source axial caps mostly ?
Do you know of Tedss ?
http://www.tedss.com/Capacitors

Never heard of Ted's I checked there and they have basically the exact capacitor at 820 uF instead of 750 uF. What concerns me is the pricing - there ain't any on that one - it just says to "request pricing. A sangamo on the same page at a voltage rating of 75V goes for $50 EACH! I'm afraid his prices at least on these would be just ridiculous.

But perhaps I shouldn't bother, the caps test OK and I've been advised, although they are original, to not worry about them if they test good. I did get the transistors today so the parts are coming in. Due to Memorial day no more parts till at least Tue.

I did get a sweet DC503A in to play with in the mean time (which actually works)  :clap:
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RF, Microwave, HAM Radio / Re: Small radio receiver project
« Last post by cdev on Today at 09:05:58 AM »
Good suggestion!

The keyword to use to get started is pa0rdt mini whip, because I think that is where the design originated or was first popularized. but there are many variations.
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Test Equipment / Re: Handheld meter electrical robustness testing.
« Last post by joeqsmith on Today at 09:05:55 AM »
Don't link me your meter on a rope video.
Says the guy who climbs on the roof of his house to throw meters off it.  :popcorn:
Didn't see any throwing.....just careful release (liberation) into the atmosphere.

That in itself is also valid information to add to the choice of a DMM to buy...........those that can be clipped back together and continue to be used.  :phew:

Since 5KY's UT61E was dropped from the roof, I used it to show:

How much current the meter could handle if you short out the fuse
What happens when you jumper out a fuse with wire
Used it for target practice with my jumped fuse rocket
Test the amount of current seen by the controller IC during an ESD event and how to protect for it
Used the shunt to see how much current it could carry and help design a new shunt
Used it to mock up a low burden voltage circuit

Too much work to make a list...
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Pleased with your Chargemaster kj7e ?
Got one a few months back and I'm very pleased with mine after the dispensing tube mod.  :)
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Projects, Designs, and Technical Stuff / Super High Frequency TC
« Last post by IanBerry on Today at 09:02:27 AM »
Hello, I've been designing a project for awhile to kind of push the limits of a Tesla coil. My goal is to drive a coil at somewhere around 100MHz. Though, I'm a little hesitant to construct the circuit because I'm worried that things won't function normally at such a high frequency. All of the components are rated for that kind of frequency, I'm just still unsure. Like in the bootstrapped H-bridge, I kind of pulled the capacitor value right out of my rear end since I'm not very familiar with them and I don't know what capacitor values work with what frequencies. As well as using 2n904/2n3906 as my MOSFET driver/bootstrap driver. Also, I'm worried about voltage spikes and I was thinking with the parasitic diodes of the MOSFETs and a large input capacitor those spikes could be absorbed. I also might have to put a capacitor in series with the Tesla coil primary to counteract some of the inductive reactance at such a high frequency. Just in general, I was hoping someone could look over the circuit plan and point out any flaws or give some suggestions. I attached a picture of my drawn out circuit. (Please excuse the cursive.)
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But if you have the spare supply voltage, and transistor amperage, to direct drive it, why not do that? ;D

That's also something we did: a direct drive induction heater.  The size of a small walk-in refrigerator, and all that work just for 150kW.  And yeah, 150kW, it can heat up a hunk of steel in a hurry (or the outside, anyway), but there was >1MVA of IGBTs in the sucker.

And yeah, economy of scale is against you when your inverter modules are a few kilobucks a pop, and it's less of a big deal when you're comparing a $1 transistor to a $0.20 capacitor.  But then again, if you're making only 10,000 of them, that's a kilobuck of savings to be had...

Tim
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Altium Designer / Re: Altium Cancel Circuit Maker Newsletter
« Last post by Joel_l on Today at 09:00:02 AM »
Someone else had written a script to do that, worked well It grabs everything on the design content live site. Did not take a real long time.
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