John Wiltrout's Blog

Vacuum Chamber for Pulling Wires through a Sheath

jw0752 — Mon, 05 Dec 2022 02:21:44 GMT

This is my first Blog in over a year so you will probably not see any improvement in my style or deliver from previous attempts. I have a hobby business where I repair or recondition specific parts for various pieces of Dental Operatory Equipment. On...(read more)

Grafting 2 Damaged Circuit Boards

jw0752 — Sun, 16 May 2021 17:52:02 GMT

In the picture above we have two circuit boards from two Dental Table Top Sterilizers. The board on the left has had a solder joint crystallize, arc out, and set fire to the back of the board. The board's logic section is still working properly b...(read more)

Solder Wick Repair of Damaged Circuit Board

jw0752 — Wed, 03 Feb 2021 15:20:39 GMT

The circuit boards used in the counter top sterilizers of the medical and dental industries are subjected to a lot of stresses. The high moisture content in the air combined with the heating and cooling inherent in their operation puts them at higher...(read more)

Climate Change Anyone?

jw0752 — Tue, 20 Oct 2020 23:42:20 GMT

This is about 5 weeks early even for us: Slip or get your feet wet I refuse to shovel in October! John(read more)

Repair of a Burned Circuit Board using Grafting Technique

jw0752 — Wed, 30 Sep 2020 05:59:28 GMT

This is the main circuit board from a Dental Clinic Sterilizer. It is a very popular brand that has been sold extensively across the USA as well as internationally. One of the power outputs of the board is controlled by a 30 amp relay that powe...(read more)

Lie Detector Fact Checker and Commentator

jw0752 — Sun, 23 Aug 2020 05:18:43 GMT

Recently I have been having a hard time watching my television. There are a lot of people on the TV lately who like to make up things and tell lies or at least bend the truth around so that one can not tell which end of the horse to kiss. These alter...(read more)

How I poked out an Eye of my Oscilloscope - A cautionary tale

jw0752 — Wed, 19 Aug 2020 05:33:26 GMT

For about a year I have owned a Hantek 8060 dual channel oscilloscope. I have been very pleased with the scope as it is well suited to my needs. I use it in my simple experiments and I use it for helping me diagnose equipment that is in need of repai...(read more)

Repairing an Inexpensive Scope Probe

jw0752 — Tue, 18 Aug 2020 21:22:34 GMT

Recently my scope and I had an unfortunate encounter with some high voltage and it left me with one channel out. I am slowly working through the process to see if I can fix the scope. I will blog about my journey at a later date whether I can fix it ...(read more)

A Do Nothing Machine

jw0752 — Sat, 20 Jun 2020 21:15:27 GMT

The Thinker Revisited The Thinker Revisited is an Electronic Sculpture built on an X-Ray Control circuit board. I usually salvage these boards for the parts but since I had already taken a ...(read more)

World Tour

jw0752 — Fri, 12 Jun 2020 23:29:17 GMT

I got the idea for this Blog from jancumps . Since the Covid 19 has kept us from getting out and traveling I thought it might be fun to give you a short tour of my home town Chippewa Falls Wisconsin USA and to invite you to add your own tour of your ...(read more)

Anyone seen circuit modules like this before?

jw0752 — Fri, 03 Apr 2020 19:40:35 GMT

I am busy salvaging circuit boards while my mind resets and a new idea for a build takes form. Yesterday I disassembled a circuit board from a Planmeca X-Ray machine (a company from Finland) that dated from the 1990s. Among the salvaged components we...(read more)

Playing with Circuit Boards while the Virus Storm Passes

jw0752 — Mon, 30 Mar 2020 23:11:35 GMT

I am very lucky to have a son in the Dental Equipment Service Business who faithfully watches for circuit boards that he can salvage from discarded equipment and deliver to the old man (me). Here is the cache that I got on Friday. Sometime...(read more)

Making a Load Bulb for Board Output Testing

jw0752 — Tue, 24 Mar 2020 15:05:20 GMT

Today I am working on a circuit board from a Dental Statim Sterilizer. This sterilizer is unique in that it doesn't work by heating water inside the sterilization chamber but rather it has a separate boiler. Water is injected into the boiler and ...(read more)

AC Optocoupler LTV 814

jw0752 — Sat, 22 Feb 2020 06:21:41 GMT

When I used to repair dental chairs it was very common to find a logic circuit communicating with a line voltage triac through an opto-coupler. The chair's actuators were typically 115 Volt AC motors. These opto couplers had an internal LED tied to a...(read more)

One of My Favorite Building Blocks

jw0752 — Sun, 16 Feb 2020 07:59:14 GMT

I like to think of the parts and pieces in my shop as building blocks. I very seldom design my creations from the ground up. Like the Borg, I prefer to assimilate technology. Once I have a board or circuit that I find a useful building block I go to ...(read more)