Resistance Check on 52

[Emoreigns]

Good Morning,

My build on the BeePre has been going pretty smoothly up until now- I made it to the resistance check on page 52, but have come to a stop here. I am not getting any reading with my meter for either of the resistance checks- It is just showing the 0L reading, which I believe means the circuit isn't completed?  There are some joints that are not soldered yet, so perhaps those are the problem? My multimeter works fine for testing resistors, so I don't believe that it is the problem. I've attached a couple pictures. I appreciate the help as always! Am I just overlooking something here?

 

[kgoss]

0L is actually over limit. If you don’t have an auto ranging meter you need to increase the range to one greater than the resistance you are measuring. To test your meter just measure a known value resistor out of the circuit and see if you get the correct value. Just be aware the value you read might not be exactly right because of part tolerances. But it should be very close.

 

[Emoreigns]

Thanks Ken-

The value for A1 and A4 are supposed to be 445 ohms each- So I had my multimeter set to 4000- I(t goes 400,4000,40000) So anyways, the A1 terminal is right on 445 ohms, but I wasn't getting a reading on A4. I took your advise and cranked it up to 40000k and now it is reading 25.03-

It was getting late when I soldered this, and I've already found a couple joints that weren't soldered that should have been. Thanks for the tip on the meeting though- I knew it was something simple, but just couldn't put my finger on it. Still very much a soldering noob-  Hopefully I can find what the issue is tonight-

 

[Paul Birkeland]

You may just need to crimp the unsoldered ends of those resistors down a little bit may help pull that reading into spec.

 

[Emoreigns]

I crimped those resistors down as best as possible- Still not getting a proper reading… still not reading at 4000, and coming in at 25.0 on 40000 ohm setting. My readings seem steady elsewhere.

 

[Paul Birkeland]

The purpose of this resistance check is to be sure that the 330 Ohm resistor goes in the correct spot and doesn't get swapped with one of the 130 ohm resistors.  Since we can see that your 330 ohm resistor is in the correct spot, I would go ahead and continue with the build.  I suspect that as you complete that section and have all those terminals soldered up that you will end up with the correct resistance readings. 

-PB

 

[Emoreigns]

Ok Great Paul-

That was my gut instinct a few days ago, but I figured it best to consult with the experts and make sure I hadn't made a glaring mistake, or was going to damage something-

Thanks for the help as always- I will update at the next voltage/resistance check or completion to confirm that those values came into spec.

 

[Emoreigns]

Morning Paul,

I continued on per our last conversation until I came to the voltage test- I didn't want to power up before confirming that is OK to proceed.

The A4 & B4 terminal values are still off- A4 is still reading at 25 @ 40k and B4 was reading 80 @ 400k-

There are still some unsoldered wires on 9 and 15 I believe, but I'm not sure if that is the issue or not...

Thanks for all the help!

 

[Paul Birkeland]

You can clip the black probe of your meter to terminal 26 to make these measurements and that should rule out the other stuff upstream.

 

[Emoreigns]

Ya, still coming back with issues when the black probe is attached to 26. B1 was good right at 445- But B4 still was coming back 80.0 @ 400k setting. Not sure what to make of this-

 

[Paul Birkeland]

Can you verify the resistance of the 130 ohm resistors?  You should be able to just measure across them with your meter with no 300B in the socket.

Also verify that the resistor attached to B4 is reading correctly.

 

[Emoreigns]

The 4-130’s are reading 117.2-117.8

B4 is 218 measured the same way

 

[Emoreigns]

Does this tell you anything Paul? These values seem to be correct, and double checking it looks like I've got all the resistors in the right spots. I just cant figure out why my resistance readings are so off...

 

[Paul Birkeland]

If you can measure the 330 ohm resistor while it's mounted in the kit and it measures correctly, then try to measure that resistance across the terminals it's mounted to.  Does that resistance appear at those terminals?  Now try this for each of the 130 ohm resistors.  At some point, you will get a resistance reading on a resistor that doesn't agree with the resistance reading between the two terminals it's mounted to, and that's an indication of a soldering issue or a broken lead.

 

[Emoreigns]

Good Morning Paul,

Am I just looking at the (2) 130 ohm resistors and the (1) 330 ohm resistor  for each tube? Or is there somewhere else I need to verify too-

Because, After triple checking  these 6 resistors ( 4 130 ohm and 2 330 ohm) I am positive the resistance readings across the resistors themselves, and the terminals they are soldered to are the same?

Perhaps I am just not looking at the right spot? Probably just another noob move out of me here-

 

[Paul Birkeland]

If the resistance readings are good, be sure to check the resistors going to the tube socket pins themselves.

 

[Emoreigns]

Paul, all resistors to the pins seem good too- Only thing I can think of is maybe I accidentally installed the potentiometers wrong… Could this explain the incorrect readings? I attached a photo of the potentiometers- Thanks Paul

 

[Paul Birkeland]

I can't think of a way for the potentiometers to cause an issue.  If the resistors all measure correctly and the terminals where the resistors are soldered to show the proper resistances, that would contradict the information initially presented.

 

[Emoreigns]

Perhaps I am misinterpreting something Paul- I will make a detailed exhibit with some marked up photos of the readings I am getting tonight, and hopefully that will assist in the diagnostic.

Thanks again,

 

[Emoreigns]

Alright- I marked up everything from the previous resistance checks, from the manual, and that you asked me to do Paul! Hopefully this can shine some light on where I went wrong! I  am dying being stuck so close to the finish line on this one!

Thanks as always!