slipped while cutting/stripping wire....

madbrayniak · 13295

0 Members and 1 Guest are viewing this topic.

Offline madbrayniak

  • Full Member
  • ***
    • Posts: 110
Reply #45 on: May 09, 2012, 09:15:20 AM
This is incorrect. The MJE 350 always goes in the same way. That post you are referring to is about one batch of transistors we got, that looked a little different. They still go in the same way.  You may be confusing this with the orientation of the MJE5731A transistor, which is not used in this kit

I am confused.  In the manual the grey face points to the edge of the board correct?



Offline madbrayniak

  • Full Member
  • ***
    • Posts: 110
Reply #46 on: May 09, 2012, 09:23:55 AM
i have about 35.5V at IB and IA but OB and OA are only reading 0.8

on the transistor I am getting from left to right when looking a the silver side of the transistor.....35.5-0.8-25.4 on both sides approximately.

Which makes me wonder, shoul I move the OB and OA wires to the outer most position? I soldered them exactly as it is in the manual but if I moved it to the outer OB and OA then maybe that will fix the problem?



Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #47 on: May 09, 2012, 09:48:36 AM
Paul Joppa, PJ, is the designer of the "PJ" CCS board.  It is best to answer his questions and he can suss out your problems.  Mine was that I didn't solder one of the transistor leads, Duh!, way back when I put the C4S into my Paramours.

To borrow a phrase from "Loud Steve" at VSAC 2003, Paul Joppa is, "The Man."  You had to be at dinner with us to understand this.



Offline Doc B.

  • Administrator
  • Hero Member
  • *****
    • Posts: 9680
    • Bottlehead
Reply #48 on: May 09, 2012, 10:09:51 AM
This is incorrect. The MJE 350 always goes in the same way. That post you are referring to is about one batch of transistors we got, that looked a little different. They still go in the same way.  You may be confusing this with the orientation of the MJE5731A transistor, which is not used in this kit

I am confused.  In the manual the grey face points to the edge of the board correct?

The MJE350 installs exactly as shown in the photo in the manual. The post that was referenced had to do with a batch of transistors we got a long time ago that looked a little different. Please disregard that. The current MJE350s look like the ones in the manual and install exactly the same way.

If you have voltage to the board and no voltage at the plate of the tube it is likely that on the PC board something is miswired, there is a bad solder joint, or something is installed backwards. Sometimes it helps to have someone else look over the board and compare it to the photo in the manual. It's easy for our eyes to miss something after we have been staring at it for a while.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline Paul Joppa

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 5847
Reply #49 on: May 09, 2012, 10:57:36 AM
i have about 35.5V at IB and IA but OB and OA are only reading 0.8

on the transistor I am getting from left to right when looking a the silver side of the transistor.....35.5-0.8-25.4 on both sides approximately.

Which makes me wonder, shoul I move the OB and OA wires to the outer most position? I soldered them exactly as it is in the manual but if I moved it to the outer OB and OA then maybe that will fix the problem?
The emitter, the rightmost terminal, should be slightly higher than the base which is leftmost. (If you look closely, you will see B-C-E marks next to the terminals; C is for Collector.)

This indicates that the 470 ohm resistor, which sets the current and connects the emitter to the IB or IA terminal, is not connected properly. Or the resistor may be the wrong value - that's why I keep suggesting you measure the resistance of the resistors. If your meter won't measure resistance, you could replace the resistor with a new one and see if it changes things. It does not need to be a precision part, 5% accuracy is widely available and perfectly fine.
« Last Edit: May 09, 2012, 10:59:50 AM by Paul Joppa »

Paul Joppa


Offline madbrayniak

  • Full Member
  • ***
    • Posts: 110
Reply #50 on: May 09, 2012, 12:31:53 PM
Doc, Ill get a friend to see if he can figure it out if I dont get it going today....i agree about looking at things for too long...sometimes its best to just take a step back.

Especially when it is somthing this small.

Paul,  sorry I didnt get the resistance earlier I was trying to find the manual to figure out how to do the resistance check....looked all over the entire house and garage and it wound up being in the rubber cover of my meter....woops!

weird thing is that as soon as I turn the dial to the "omega" sign there is a 1 on the screen....it kinda looks like this

[1   .   ] with [] being the edges of the screen. 

on IA side I am getting 177 but its kinda jumping all over the place but that may be my jitter

on IB I get 172 or so as well but also jumps around a bit...

I am testing it with the positive and negative touching oposite leads on the resistor as that is how I understood to do it.....



Offline madbrayniak

  • Full Member
  • ***
    • Posts: 110
Reply #51 on: May 19, 2012, 10:22:44 AM
quick update,

I moved the red wire from the inner most OB and OA and now I am getting some music but it is really quiet.  Like so quiet that and highest volume its wisper quiet. 

Paul,  I havent had time to do the resistance check yet as I am going to have a friend help me with that when he gets a chance.

However, he said that the resistors need to be desoldered from the board....is that right?



Offline Paul Joppa

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 5847
Reply #52 on: May 19, 2012, 12:30:33 PM
Depending on the meter, you might not need to unsolder anything. The transistor base-emitter junction is in the opposite direction from the diode, so if everything is wired correctly there is no opportunity for leakage currents through the rest of the circuit to affect the resistance readings.

Just to be sure, you should read the same resistance with the meter leads reversed.

Paul Joppa


Offline madbrayniak

  • Full Member
  • ***
    • Posts: 110
Reply #53 on: May 21, 2012, 06:37:27 AM
ITS ALIVE!

So I did indeed have the resistors mixed up.  the 470K Ohm and the 470 Ohm were reversed.  So I changed those out and boy does this baby sing!

I was amazed at how much base was more present  in my stereo setup with it fixed.  It also plays louder now too.

I feel really stupid for making such a dumb mistake....

but atleast I can say I am just a rookie



Offline corndog71

  • Sr. Member
  • ****
    • Posts: 593
Reply #54 on: May 21, 2012, 09:47:30 AM
Don't beat yourself up too much.  Been there many times.  It's all part of the learning experience.  Now you can bask in the awesomeness! ;D
« Last Edit: May 23, 2012, 07:01:23 AM by corndog71 »

The world was made for those not cursed with self-awareness.

Rob


Offline madbrayniak

  • Full Member
  • ***
    • Posts: 110
Reply #55 on: May 22, 2012, 03:22:21 PM
OH I AM!

I am currently listening to Pink Floyd: Dark Side of the Moon.

However, as I am listening I got to thinking.

It would be nice to mount everything on a metal plate that was nice and polished.  However, I continued to think and does anyone on here know where you can get a metal plate that has the "spotting" done to it?

I dont really know what else to call it....like what you see on this watch movement...

http://www.google.com/imgres?q=watch+movements&start=135&um=1&hl=en&qscrl=1&nord=1&rlz=1T4ADFA_enUS482US482&biw=1309&bih=882&tbm=isch&tbnid=EfGIji3WKIKdKM:&imgrefurl=http://www.savvywatch.com/info/Watch_Movements&docid=aiLebj7uyaZCBM&imgurl=http://www.savvywatch.com/media/Site%252520Files/Theme%252520Files/Active%252520Theme/Images/common/movements.jpg&w=286&h=447&ei=eTu8T7ydG6WViQLNnOWIDg&zoom=1&iact=hc&vpx=178&vpy=199&dur=1701&hovh=281&hovw=179&tx=83&ty=185&sig=111633928306654150022&page=6&tbnh=156&tbnw=98&ndsp=30&ved=1t:429,r:24,s:135,i:183


Was thinking that doing that with the batteries mounted below in a black wood base would look fantasic with the plate finished nicely



Offline Wanderer

  • Full Member
  • ***
    • Posts: 210
Reply #56 on: May 22, 2012, 05:22:17 PM
OH I AM!

.....It would be nice to mount everything on a metal plate that was nice and polished.  However, I continued to think and does anyone on here know where you can get a metal plate that has the "spotting" done to it?

I dont really know what else to call it....

It is called "engine turning" or "Jeweling"

....BUT I seem to recall the use of the plastic top plate on the Quickie is to help control the microphonics of the tubes. 

Kevin R-M


Offline Paul Joppa

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 5847
Reply #57 on: May 22, 2012, 05:34:28 PM
....BUT I seem to recall the use of the plastic top plate on the Quickie is to help control the microphonics of the tubes. 
Haha! Actually, the plastic is just cheaper, making the low low price possible. The vibration control is a happy accident.  :^)

But yes, a really nice chassis would be pretty cool. Fortunately the plate is pretty simple; anyone who could produce an engine turned plate could probably also put the appropriate holes in that plate, too.

There ARE vibration-isolation sockets - or at least there used to be. If you can find some whose rubber has not rotted or fossilized, they could be equal or better at microphonic control. Or invent your own - your local hardware store has lots of rubber washers'n'stuff. Doc B invented a pretty cool one for 845s; maybe it would be adaptable to smaller tubes?  :^)

Paul Joppa


Offline madbrayniak

  • Full Member
  • ***
    • Posts: 110
Reply #58 on: May 23, 2012, 08:13:53 AM
so in a ways I need to just figure out a way to float  or decouple the socket from the plate?



Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #59 on: May 23, 2012, 08:33:24 AM
   .  .  .   
Or invent your own - your local hardware store has lots of rubber washers'n'stuff. Doc B invented a pretty cool one for 845s; maybe it would be adaptable to smaller tubes?  :^)

I'm a big fan of O-Rings.  You can make a tube socket float with small O-Rings around the mounting screws and a big one just outside the hole for the tube socket.