- 'scope clock advice please - 11 Updates
- Hickok 440 Curve Tracer Repair Help - 1 Update
| etpm@whidbey.com: Jun 27 04:28PM -0700 Well, I've been gone for a month and this group is dead. So maybe my questions will liven it up some. Or maybe everyone else is also on vacation. I know, this is a repair group. But I will no doubt need to repair whatever I build. And besides, I get better electronics advice here, as in more of it and correct, than on the basics group. While wasting some time on the computer while being on hold I came across some small ocsilloscope CRTs, then looking for something to light one of them up I saw some kits to make oscilloscope clocks. Only 34 bucks for the kit! So I ordered a two inch CRT with electrostatic deflection. Here's a link to the CRT I ordered: https://www.ebay.com/itm/5LO38I-Mini-5-cm-CRT-oscilloscope-cathode-ray-tube-FOR-DIY-NOS-BOXED/111978397405?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3Da8915a4a567c484c94f5f3b2d9e743c4%26pid%3D100675%26rk%3D4%26rkt%3D15%26mehot%3Dag%26sd%3D401706260380%26itm%3D111978397405&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3Afb320543-9930-11e9-9594-74dbd1808485%7Cparentrq%3A9b35da7016b0aa19f93d280effb7f16e%7Ciid%3A1 Then on to ordering the kit. Hah! No dice. The kits are no longer available. But I think I can still download the code for the microcontrollers and the files for the circuit boards. Here is a link to the page that the kit used to be available from: http://www.dutchtronix.com/ScopeClockH3-1-Enhanced.htm The kit was also available from other sources but I can't find it for sale anywhere. Darn. Maybe someone here bought one of these kits and never built it and it is collecting dust. If so why not sell it to me? I also need to drive the CRT and I found a simple circuit called the Mullard's Pupil Oscilloscope. Here's a link: https://www.instructables.com/id/Mullard-Pupils-Oscilloscope/ So, if I build the Mullard scope circuit will it drive the two inch CRT I ordered seeing as how it was made to drive a 1 inch CRT? And if that works will the Dutchtronix clock circuit work with the Mullard scope and give me a nice looking display? Look, this is just for fun. I am capable of safely dealing with the high voltage. But I don't know enough to know if all the parts will play nice with each other. I have also not built any tube or valve gear using point to point wiring so a little advice about that would be greatly appreciated. When it is all done the idea is to have as much of the tube circuitry as possible exposed with the modern microntroller stuff hidden away. I like tube stuff and exposed machinery, always have. I think a one tube scope with a hand wound xmfr could look pretty cool sitting on a shelf near my tube amplifier. Thanks All, Eric |
| dplatt@coop.radagast.org (Dave Platt): Jun 27 04:53PM -0700 In article <bkiahetm7sd5tu5le62altohhbp9vnevra@4ax.com>, >inch CRT I ordered seeing as how it was made to drive a 1 inch CRT? >And if that works will the Dutchtronix clock circuit work with the >Mullard scope and give me a nice looking display? Maybe. :-) In principle it ought to work, if you get the voltages correct. If you don't, it'll either not work, or damage the CRT or something else. Among the things you'll need to look at, in matching up the various circuits and components, are; - The required heater (filament) voltage and current for the CRT you are using. - The cathode, grid and deflection voltages for the CRT you are using. - The voltages being created by the clock circuit (microprocessor) and being fed to the X and Y inputs of the scope circuit Read through the data sheet for the DH3-91 CRT that the circuit was designed to work with (http://www.labguysworld.com/1CP1(db3-91).pdf) and for the CRT you bought. The physical size of the CRT doesn't matter very much (directly) but a larger or different CRT may have different voltage or current requirements. |
| John Robertson <spam@flippers.com>: Jun 27 04:57PM -0700 > cool sitting on a shelf near my tube amplifier. > Thanks All, > Eric Looks like a fun project! Make some PCBs and offer them here, I'd probably buy one just for fun. I've got a few 'scopes sitting around that aren't doing anything useful... As for the Mullard scope, it should work with a larger tube, you just may have to raise the deflection voltage a bit. Find the specs on the two tubes to see what the deflection differences are - if any! John :-#)# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out." |
| Phil Allison <pallison49@gmail.com>: Jun 27 07:05PM -0700 > https://www.instructables.com/id/Mullard-Pupils-Oscilloscope/ ** No pics or diagram showing up for me. Am I missing something? .... Phil |
| Rheilly Phoull <rheilly@bigslong.com>: Jun 28 10:59AM +0800 On 28/06/2019 10:05 am, Phil Allison wrote: > .... Phil Might pay to check around, comes up OK for me in Oz |
| Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Jun 28 05:49AM +0200 On 28.06.19 4:05, Phil Allison wrote: > Am I missing something? > .... Phil Loads fine here(Netherlands). Interesting circiut diagram. Needs a few mods, if you dont want a 12v supply. |
| Phil Allison <pallison49@gmail.com>: Jun 28 01:14AM -0700 Sjouke Burry wrote: > Loads fine here(Netherlands). ** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one. Could that be it ? .... Phil |
| Jeff Layman <jmlayman@invalid.invalid>: Jun 28 09:55AM +0100 On 28/06/19 09:14, Phil Allison wrote: > ** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one. > Could that be it ? > .... Phil I doubt it. I am using an adblocker and see the page without problem. I don't know what browser you are using, but try using it with all add-ons disabled ("Safe Mode" when using Firefox, for instance). If that allows you to see the page, you have to go back to normal mode and switch each off add-on in turn until you find the one which is stopping the page from displaying. -- Jeff |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Jun 28 03:59AM -0700 http://oscilloscopeclocknixiecrt.com/Kit.htm https://makezine.com/2007/05/30/35-avr-oscilloscope-clock/ Peter Wieck Melrose Park, PA |
| John-Del <ohger1s@gmail.com>: Jun 28 04:36AM -0700 On Friday, June 28, 2019 at 4:14:28 AM UTC-4, Phil Allison wrote: > ** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one. > Could that be it ? > .... Phil Odd.. You can try converting the web page to a .pdf right on line. If you can open this: https://webpagetopdf.com/ or one the many like it, input the instructables url and it will convert it to .pdf. |
| Geo <nhhu-o3hu@dea.spamcon.org>: Jun 28 04:06PM +0100 https://www.ebay.com/itm/Oscilloscope-Clock-Kit-for-many-crt-types-Wifi-OR-gps-CRT-Cathode-ray-tube-Scope/303198819933?hash=item46980ed65d:g:84wAAOSw3dxbTimZ |
| Don Brown <edfredcorp@gmail.com>: Jun 27 11:29AM -0700 On Wednesday, June 26, 2019 at 9:10:30 PM UTC-7, Don Brown wrote: > I took some photos of when it is at it's best: > Here is a sample curve trace - http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickok%20440%20Curve%20Test%20Scope%20Screenshot%20Working.jpg > Here is the calibration screen, fairly normal I think with two steps per division as expected - http://www.edfredcorp.com/Hickok/httphotos/Hickok_20440_20Schematic_20_26_20Circuit_20Description/Hickok%20440%20Calibration%20Scope%20Screenshot%20Working.jpg OK, it has been stable for hours. I repeatedly cleaned and worked all switches and adjusted component clearances to avoid possible touching to case. Also gently flexed the pc board looking for sources of intermittent signs. Maybe the non electrolytic capacitors needed time to reform, though I did not think it mattered to those. At this point I did not address the 13v-14v power supply deficit, since it seems to be working. If anybody thinks I should address that for better precision, I will. Also now have the Heathkit manual for review. Thanks for all the tips from everybody. |
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