Jonny Guru + Caps

[TheLaw]

Well what happened here?

http://www.jonnyguru.com/modules.php...ory4&ndar_id=8

[Scenic]

Re: Jonny Guru + Caps

my first guess would be too low ESR (or too high? well probably not.. but certainly not the same as those fuhjyyus and capxons)

[Per Hansson]

Re: Jonny Guru + Caps

I know this was discussed either here or on Jonnyguru's forums before.
I have not looked up the specs of the capacitors used but it would be my guess that they ventured too far from the originals specifications.

The capacitors and inductors in a PSU form a filter, so called "Pi Filter".
Thus the capacitors and the inductors (which is what the Pi Filter is) must be matched.
So ESR, Ripple and Capacitance is choosen according to the size of the inductors...

P.S: Inductors are often referred to as "Coils" aswell

[Toasty]

Re: Jonny Guru + Caps

I was always of the opinion that something else had changed when JG did that. My reason was, the waveforms are really whacked compared to the originals.

I could understand/agree with the change in ESR causing the screwy waveforms, -if- the waveforms looked like the originals, only "bigger". These look like something is inducing interference into the signal. Like a bad scope probe or frayed (or too long) ground braid...?

He does say that the testing was done "in two phases several weeks apart"...?

I've used all FM's to recap units and not had that kind of result. [Antec]

I will try using HZ's when I get a unit I think deserves them , just to see.

Could this be more due to poor(ly made) inductors than caps?

Need a plug-n-play PSU with a selection of components to swap in and out to really be sure.

Toast

EDIT: Afterthought... Fluorescent light fixture electronic ballast in lab causing the extraneous "noise". I've had that experience and now do some low level testing with them off and just incandescent bulbs for lighting.

[PCBONEZ]

Re: Jonny Guru + Caps

Per Hansson's got it right.
- And now you have an example via o'scope of why I harp on matching specs.

It's on page 1.
He (it was Oklahoma Wolf) used KZE and KY which aren't even close to the ESR/Ripple of some of the original caps.
He didn't even check the specs on the old ones. [I asked him.]
He just went with Jap caps...
- - And in the process changed the frequency response of the pi circuits.
.
Note that it was done 4 years ago.
What he did was standard practice 4 years ago. (Every place except BCN that is.)
It's STILL standard practice/advice in most places.

WE MUST TEACH THE WORLD!!
[Okay, that's silly...]
.
.

[Scenic]

Re: Jonny Guru + Caps

KZE and KY vs. fuhjyyu TMR and TNR and Capxon KF (from what i can see)

[Mad_Professor]

Re: Jonny Guru + Caps

I was wondering why he was using such crappy caps to begin with, UCC wouldn't be my first chose, I would have gone with Panasonic or Nichicon. If he had gone with those maybe the results would be different?

[Per Hansson]

Re: Jonny Guru + Caps

UCC is not a crappy brand, they make great caps.
Just because they have been bitten by a bad series (KZG) does not mean they do not make good caps.
Hell if we stopped using caps from manufacturers that have never created duds we would have an extremely limited supply!

[smason]

Re: Jonny Guru + Caps

I agree with Toast, looks like extraneous interference on the scope. Bad ground or probe.

[brethin]

Re: Jonny Guru + Caps

Read the article in detail and you will see he states he does not have a ESR meter so he has no clue if the caps he put in are good (yes even new ones can be bad). My first guess would be a bad cap got put in.

[Toasty]

Re: Jonny Guru + Caps

Does anyone have the Fuhjyyu TMR / TNR datasheets?

The only ones I see now on their site are TM / TN.

Mad_P - {fwiw} Generally high to lower (not good to bad, mind you):
P-FM, U-KZE, N-HE, U-KY, P-FC
when looking at the same value and can size.

It also depends on how sharp a point you want on your pencil.

You can drive yourself nuts over milliohms and 10's of milliamps of difference. What it comes down to when you choose caps for a project/repair is: which ones are "close enough" then "who has them and at what price?"

Toast

[PCBONEZ]

Re: Jonny Guru + Caps

TM = TMR
TN = TNR
The R is a marketing thing.

I think it may mean custom ordered size.
The TMR 4700uF/10v that came out of the TP-II(s) I did were 10mm x 40mm I think.
Maybe it was 10x35mm, but anyway, the actual size was longer than the data sheet.
[Same with the 3300uF/16v.]

[Toasty]

Re: Jonny Guru + Caps

Okay. Sleeve colors TMR/TNR don't match the new(er) sheets.

[PCBONEZ]

Re: Jonny Guru + Caps

I think jonnyguru probably knows how to use a scope.
.

[PCBONEZ]

Re: Jonny Guru + Caps

From what I can tell the sheets they have on-line match those I have on file which are older than that little experiment.
TM are blue.
TN are black.

Either that or I dunno what you are looking at...
.

[PCBONEZ]

Re: Jonny Guru + Caps

Appears they didn't do a full recap too.
If I remember right that TN is on +5vsb.
.

[Toasty]

Re: Jonny Guru + Caps

http://www.fuhjyyu.com.tw/pro.htm

TM at far right column shows "Royal Brown".

TN is black as was TNR.

The TN, IIRC, is on the -12v in, then the Little (magnifiers everyone over 40) coil behind it, then the KY/KZE to the Blue wire.

[PCBONEZ]

Re: Jonny Guru + Caps

Yet photo in actual data sheet is Royal Blue.
I think maybe that's a typo.
Not sure though, I -may- have seen brown ones at some point.
.

[Toasty]

Re: Jonny Guru + Caps

Yeah, never heard of that color. The last Royal Brown was followed by a flushing sound...

[PCBONEZ]

Re: Jonny Guru + Caps

There IS a band called Royal Brown,,,, perhaps they sound like sh*t.
.