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FrozenGate by Avery

Kenometer laser power meter interest. LITE version *closed*






Kenom said:
it is similair laserbee. Instead of your solution which only calls for a pair of electrolytic capacitors on the outputs of the dc/dc converter, this new setup also calls for 2 pair of bypass ceramic capacitors. both on the input and the output. 1 .01uF ceramic and 1 .1uF ceramic in series on both the input and output. so that's 3 pairs total. Ok I'm confusing myself. you have one 5v input that needs 1 .01uF and a .1uF in series. then your ±9v out requires a set of .1 and .01uF capacitors on each of the outputs. +9v and -9v.

So in reality, you've got 3 capacitors on the output using the electrolytic capacitors as well which are rated at 100uF 25v.
Click to expand...

I still have to finish assembling my kenometer, but i just realized that the meters are having problems. Should I bother assembling it now or will you send me parts to fix the problems?
 
yours utilizes a PSU and is not prone to problems with the dc/dc converters.
 
well, the only thing I'm waiting on for the pro's are the overlays that are being printed. I told them to print them on the 24th so I should get them any day now.
 
Hi Ken,

Sorry to hear about your recent difficulties. I hope they turn out to be mere bumps on your road to success.

As you already know, a number of us Kenometer Lite purchasers are still patiently awaiting the finished products to appear in our mailboxes.

If possible, please keep us updated here (I'm using this thread since it was the original Kenometer Lite purchase thread) on any estimated completion/delivery dates or changes to our orders.

PM's work just fine for me, too.

Again, best of luck with all you're going through.

Mark
 
You got it. I wasn't happy with the way that the caps were filtering only a good percentage of the noise coming from the dc/dc converters. Mario ended up putting the dual dc/dc converters on his scope and saw that they were incredibly noisy so he's designed a completely new circuit which utilizes inductors as well as capacitors. I'm willing to share that circuit as well although the caps alone do filter out a good percentage. It's my personal recommendation that you use the newer filter circuit and I'm willing to forward components or $$ to purchase those components to anyone wanting to use the new circuit.
Ken
 
Kenom said:
You got it. I wasn't happy with the way that the caps were filtering only a good percentage of the noise coming from the dc/dc converters. Mario ended up putting the dual dc/dc converters on his scope and saw that they were incredibly noisy so he's designed a completely new circuit which utilizes inductors as well as capacitors. I'm willing to share that circuit as well although the caps alone do filter out a good percentage. It's my personal recommendation that you use the newer filter circuit and I'm willing to forward components or $$ to purchase those components to anyone wanting to use the new circuit.
Ken
Click to expand...

Hey Ken-
Just for clarification, will you be incorporating Mario's new circuit design into the unfinished Kenometer Lites, or is your offer for the people who have already received their Kenometer Lites?
Mark
 
I will be including it for all of the unfinished meters. It's why I didn't finish them or ship them out. However the circuit is for everyone else to incorporate as well.

circuit.jpg
 
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Kenom said:
I will be including it for all of the unfinished meters. It's why I didn't finish them or ship them out. However the circuit is for everyone else to incorporate as well.

circuit.jpg
Click to expand...

Hey Kenom....

why is the specs for the U4 Panel Meter blanked out...
are they a secret like your Thermopile heads...:thinking:
And what is the green bar in the middle of the Display
represent...:thinking:

Jerry
 
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hahah sorry, it was the mcu (was originally put together for the Kenometer pro) but will work with any setup that has the dc/dc converters.
The green line seperates the input voltage *(whatever source it may be. In the picture it was the MCU) from the panel meter since they are two different things in the Lites.

Oh and laserbee, I have verified that the single dc/dc converter is the reason you cannot get the offset circuit to work.. I wish I had realized this prior to sending those heads to you as I would have included some of the dual dc/dc converters.
 
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Got it... Thanks...

Is the MCU part number a secret... I know the FirmWare is...:D
The LaserBee I uses a PIC16F628A Micro Controler Unit..
No secrets there..



Looking at the drawing... now knowing where the power is coming in
and where the power is going out to the Thermopile Head Electronics...
I still see a problem... Your drawing shows absolutely no filtering on the
output of the DC/DC converter as I had suggested...:thinking:
They are Boost Converters and need filtering...IMO

When I originally scoped the input and output of the DC/DC converter
it was apparent that it was the Output and not the Input that was
the Problem with Ripple since the output of the DC/DC converter was
not filtered...

As I posted earlier I put a single 470mF electrolytic across the +12V and
ground output of the DC/DC converter and another 470mF electrolytic
across the -12V and ground of the DC/DC converter..
I have not yet had any more problems with my Lites....

But I can see requiring the Inductor coils when using a sensitive MCU..


Jerry
 
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The thermopile amplifier has built-in smoothing capacitors, and adding a filtering stage to the input would require more components. Ripple is now no longer visible at all on my oscilloscope for both the MCU voltage supply and the thermopile output :)
 
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