I just used a voltmeter in diode tester mode across the base and emitter of the transistor.
Some variation on the Ian Fritz method is probably a lot better.
Lol, On the Cadet IV Dual Ramp can confirm that you can simply substitute two electrolytic capacitors in parallel (5 & 10uF) to make up for the fact you ordered parts from Mouser many months ago (except for that 15uF cap that was sold out!), finally got around to your project, and your partner wants extra ramps for her performance tomorrow.
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As accurate caps are especially important for video, my query is it possibly ok to error on the side of higher voltage rating for general application unless indicated, i.e. use 24 volt rated (as it will cover the -10v/+10v voltage swing? Or even say 50v/100v? Or should i abide to the specifics of the overall BOM? Cheers!
It’s good practice to rate three times the power rails for smaller caps at least. 1u or smaller, use 50V caps. Higher voltage rating only helps the cap maintain its nominal value under load.
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thanx so much lars! <3
Also wanted to ask as all my searches have brought me to dead ends as seemingly obsolescence has taken hold, but any leads on where to source a XTAL OSC VCXO 13.5000MHZ CMOS? ooof so far zero luck. Cheers yall!
Unfortunately there aren’t any readily available sources of that VCXO unless you buy in huge bulk.
Check out this thread: [Project] Sync Generator modification
Just stumbled upon this and requested a sample! Fingers crossed it’s all good. But whoah the reverse landfill adaptor board is a real neat work around! Need to read deeper into that one though, to get all the nuances and caveats.
I am generally suspicious that any electrical components sourced from Alibabi are actually what they say they are (I’ve gotten several blacktopped counterfeit ICs before that were worthless) but hope it works!
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Hey y’all, I am zeroing in on being done with the build, at least populating the PCBs and glorious fucking day I believe I found a 13.5 MHz VXCO SMD!! Gonna have to wait till March until it arrives but I just talked to the sales rep of the company and they have assured me that it is the right part. Fingers crossed! I also made mentioned that if they are a viable resource for this part that there are many nerds interested!! I will definitely report back when they arrive and I give a proper test!
Oh yeah, almost got too excited and forgot my question. My question is I literally am down to the last set of resistor values ( CADET 9 VCO module; ((r3, 8 and 25) and I’ve bodged one of them together to make an exact 4.02 K but have not zeroed in on the other 2… mostly getting a 4.01k value with the other Frankensteined resistors. Long walk for the question, but would 4.01k suffice. Thanks, y’all.
And yes, I know I can just buy them haha anyhoo cheers folks xo
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yes 4.01k should be fine
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unless you buy very precise resistors, there will always be some difference.
normal resistors used for video circuits have 1% tolerance
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