Can I make my own probes for a B&K 415?
 

I bought a B&K 415 (together with a 1077) a few years ago and did not get any probes with them. A while back I recapped the 415 and I'd like to try my hand at learning TV alignment. Can these probes be made? If so what all is supposed to be in them?

I have at least two spare mike connectors that mate with the front panel connectors*...I also have the probe end of a B&K demodulator probe (I bought it years before the 415 to rob the rest of the cable for an old AM radio alignment gen that uses the same front panel mike connectors as the 415).

*I also have two cables that fit the front panel connectors one ends in clip leads the other in an RCA jack (I don't want to modify these since I use them with another alignment gen and an audio amp).

...

That is a very practical way to handle this. Unless one is hard set on "originality", BNC connectors do make it a lot easier.

Another vote for installing BNCs and going with standard probes.

BNC connectors fit the standard .375 holes for the mic connectors, so no drilling needed.

This B&K 415 is a TV alignment sweep/marker generator...Are oscilloscope probes even valid to use with it for any purpose?

The BNC switch would be relatively easy as I have several loose female :naughty: BNC jacks in my parts bin...

If you don't already have them you can download the schematic and operators manual here.

https://elektrotanya.com/bk-precisio.../download.html

The manual shows all the cables the unit came with. No reason you can't make your own using some RG58 coax. Agree with changing mic connectors to BNC, and I believe the hole size is the same 3/8"? You don't even need a demodulator probe if you pick off the signal after the TV's detector diode. Can't think of any reason you'd use a scope probe unless you want the attenuation. I like using a BNC to mini grabbers cable to connect in circuit. BNC to BNC for hooking to scope.

Did you get anywhere with this? I need the 300/75 Ohm cable (or a readable schematic of the probe).

I converted it to BNC and all cables except the demod cable (which I found in my junk box) and the injection cable became straight BNC to BNC. IIRC one of the manuals on the unit showed the injection cable Balun as a simple resistor network, and I didn't have the right parts on hand so I never built it.

I'm not where it's at presently so this is all memory...

The demodulator probe is about the only probe that is better bought factory if you can find it. The manual gives you an idea of how the other cables are made up. And this YT video taks about the RF out cable. https://m.youtube.com/watch?v=kRaYG-dmCPw

That video on the RF output cable is good I can probably whip that up in 15min once I dig up the parts from my junk bins.

I actually had the probe end of a B&K demodulator probe (don't know if it was for the 415) that I had chopped the coax and mic connector off of over a decade ago to use for a Heathkit color bar/test pattern generator....I had kept the demodulator end that had all the special sauce (it actually didn't look hard to copy) and just replaced the coax stub with proper new coax to make it usable again...I haven't needed it yet, but I've only tried to align one TV so far.