Author Topic: EEVblog #306 - Jim Williams Pulse Generator (Read 295388 times)

BravoV · « **Reply #275 on:** March 09, 2013, 03:43:05 am »

robrenz, what did you use to measure that 9 pS ? Thats one hell of a crazy speed there.

robrenz · « **Reply #276 on:** March 09, 2013, 03:48:14 am »

Quote from: BravoV on March 09, 2013, 03:43:05 am

robrenz, what did you use to measure that 9 pS ? Thats one hell of a crazy speed there.

I can read 9 picosecond rise time with my bare eyes and no scope needed

(It is printed on the board as the calibrated rise time)

BravoV · « **Reply #277 on:** March 09, 2013, 03:51:39 am »

LOL

, must be on the back side then, cause if you see marshallh's board few posts back, its cal-ed but nothing printed/written in there.

marshallh · « **Reply #278 on:** March 09, 2013, 05:57:46 am »

Your serial number is written in the CAL label. Mine was serial 15 but came off with isopropyl while cleaning.
The serial is used as an index so if/when Vince is able to email out the plots you can use it to tell which was yours.

He's already said what kind of results are likely:
"They range from 170pS to 210pS for a 8 vpp pulse measured at 20 to 80% into 50 ohm."

nadona · « **Reply #279 on:** March 09, 2013, 06:00:14 am »

"(It is printed on the board as the calibrated rise time) ;"

Yes, it is the serial number. My number is 53ns. Slower than my Hantek DSO;D

Thank you Vincent for the amazing work.

marshallh · « **Reply #280 on:** March 09, 2013, 06:40:43 am »

330ps fully saturating the input of my 1ghz scope (that is 0.35 / 0.33 = 1.09ghz)

And I had to try the 100mhz tek... no comparison lol

(this is through a 50ohm terminator)

EDIT: dug up the tek 464

BravoV · « **Reply #281 on:** March 09, 2013, 07:11:06 am »

Nice plots marshallh, thank you !

free_electron · « **Reply #282 on:** March 09, 2013, 06:15:00 pm »

i will post assembly instructions and the calibration data today. been busy assembling boxes and writing customs paperwork

the number written on the PCB is the serial number. don't worry if it came off with alcohol, i know who got what.

free_electron · « **Reply #283 on:** March 09, 2013, 09:36:35 pm »

The first batch of certificates is online

Serial number 4
Serial number 5
Serial number 7
Serial number 9
Serial number 12
Serial number 14
Serial number 15
Serial number 16
Serial number 17
Serial number 18
Serial number 36
Serial number 46
Serial number 53
Serial number 63

The assembly manual is here :

Assembly manual

BravoV · « **Reply #284 on:** March 10, 2013, 08:39:01 am »

Vincent, did you use the same voltage to all cal kits ? or you adjusted each until it started to avalanche ?

Also did any of those transistors toasted while testing those high voltages ? Short life as expected, but for how long ?

free_electron · « **Reply #285 on:** March 10, 2013, 04:02:03 pm »

Same voltage on all. I dropped the 24k to 20k to get consistent avalanching. The kits have the 20k resistor.

I'll post a picture of the test jig.

Havent froed a transistor yet. I had one running u til the battery was empty. Still works fine.

BravoV · « **Reply #286 on:** March 14, 2013, 03:06:27 am »

Quote from: free_electron on March 10, 2013, 04:02:03 pm

Same voltage on all. I dropped the 24k to 20k to get consistent avalanching. The kits have the 20k resistor.

I'll post a picture of the test jig.

Havent froed a transistor yet. I had one running u til the battery was empty. Still works fine.

Whats the lowest voltage that you've tested ?

nadona · « **Reply #287 on:** March 15, 2013, 05:04:18 am »

My 60 years old eyes new to SMD soldering was hesitant for a days, but finally let it go.
There is no pulse and no LED.

A different set of eyes will catch any mistakes I made.

amspire · « **Reply #288 on:** March 15, 2013, 05:19:25 am »

Looks to me like something is going between the right hand side of C6 and the top left two pins of U1

marshallh · « **Reply #289 on:** March 15, 2013, 05:21:36 am »

Very good pictures. The only thing I can see offhand is maybe a spec of solder bridging pin 1 of the Linear chip with an adjacent capacitor.
Could also be problem with the diodes' polarities. The middle diode is reversed from the others. The cathodes are very faintly marked.

You will also need a brand new coin cell. I was able to use a 4 year old cell after jumpstarting it with a 3.7v lipo. But otherwise it would not start up.

HackedFridgeMagnet · « **Reply #290 on:** March 15, 2013, 05:32:48 am »

Also L1 looks like it may have been damaged.

BravoV · « **Reply #291 on:** March 15, 2013, 05:35:14 am »

Yep, same observation as others, and its quite hard to see the diode's polarity marking even I've enhanced your photo like below.

nadona · « **Reply #292 on:** March 15, 2013, 05:41:51 am »

Putting in a brand-new battery fixed the problem! Thank you amspire and marshallh.

Is this pulse right? This is using a LeCroy LC584AL I received this afternoon.

marshallh · « **Reply #293 on:** March 15, 2013, 06:10:24 am »

Yes, it's working.. but you are using a passive x10 probe. Your measurements will be limited by this.

Set the scope to DC 50ohm input and connect the avalancher directly to the BNC. The Lecroy frontend in 50ohm mode is rated for 5V RMS but you should be fine.

sdscotto · « **Reply #294 on:** March 17, 2013, 06:16:18 pm »

Any updates on the next batch going out?

TIA

free_electron · « **Reply #295 on:** March 17, 2013, 09:40:42 pm »

next batch leaves tuesday. assembling boxes and sticking labels right now

BravoV · « **Reply #296 on:** March 18, 2013, 05:32:43 am »

Finally ... thanks Vincent !

nack · « **Reply #297 on:** March 21, 2013, 11:20:15 pm »

Darn, missed the first batch. And now I realize you have been shipping out a version two. Any possibility for me to still order a unit Vincent?

free_electron · « **Reply #298 on:** March 24, 2013, 11:03:29 pm »

And an update :

Shipment

Kit : CAL : PCB: PM : PAID : SHIPPED
alfbaz : 2x : 3x : pm : PAID : serial 48 / 58
andyturk : 1x : : pm : PAID : serial 4
Barryg41 : 1x : : PM : PAID : serial 5
biot : 1x : : PM : PAID : serial 45
BravoV 1x : 1x : : PM : PAID : serial 62 with BFG
blackknife 1x : : : pm : :
casinada : 1x : : pm : PAID : serial 18
circuitous : 1x : : pm : PAID : serial 17
Christe4nM : 1x : 1x : pm : PAID : serial 47
condor : 1x : : pm : PAID : serial 7
cyr : 1x : : pm : PAID : serial 28
echo88 1x : 1x : : pm : PAID : serial 31
enz : 1x : : pm : PAID : serial 40
EV : 2x : : pm : PAID : serial 32 / 60
fmaimon 1x : 1x : : pm : PAID : serial 50 bfg
g7psk : 1x : : PM : PAID : serial 66
gibbled 1x : : 1x : pm : PAID : shipped
grenert : 1x : : pm : PAID : serial 12
komet : 1X : : PM : PAID : serial 21
marshallh : 1x : : pm : PAID : serial 15
nadona : 1x : : pm : PAID : serial 53
Neganur : 2x : : pm : PAID : serial 43 / 54
noize : 1x : : PM : paid : serial 20
olegjay : 2x : 2x : pm : PAID : serial 63 / 16
olepr01@gmail.com 1x : : : pm : PAID : shipped
plesa 1x : : 1x : pm : PAID : shipped
robrenz : 1x : : pm : PAID : serial 9
sdscotto : 3x : : pm : PAID :
Spelunker 1x : : : pm : :
sCuba 1x : 1x : : PM : PAID : serial 49
teneyes 1x : 1x : : pm : PAID : serial 14
Tymm : 2x : 1x : pm : PAID : serial 46 / 36
Wsalden 2x : : : pm : PAID : shipped

------------------------------------
11x : 33x : 10x

Calibration Paperwork

Serial number 4
Serial number 5
Serial number 7
Serial number 9
Serial number 12
Serial number 14
Serial number 15
Serial number 16
Serial number 17
Serial number 18
Serial number 20
Serial number 21
Serial number 28
Serial number 31
Serial number 32
Serial number 36
Serial number 40
Serial number 43
Serial number 45
Serial number 46
Serial number 47
Serial number 48
Serial number 53
Serial number 54
Serial number 58
Serial number 60
Serial number 63
Serial number 66

The assembly manual is here :

Assembly manual

BravoV · « **Reply #299 on:** March 25, 2013, 03:26:20 am »

Paperwork for serial #62 ?


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Author Topic: EEVblog #306 - Jim Williams Pulse Generator (Read 295388 times)

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