Urban Ministry Live And Unplugged: Touch Plate

Saturday, July 30, 2016

Touch Plate

It's been a while since I have put an electronic design on my blog. Here's a touch plate -- I use European conventions for the circuit. Two oscillators, IC1.A and IC1.B, oscillate at roughly 30kHz. Tuned to the same frequency through P1 and P2 (ideally multi-turn presets), there is then a zero beat frequency at IC1.C output pin 10. This is assisted by a small amount of frequency lock. Touch the touch plate, and the frequency of IC1.A drops, and the frequency at IC1.C output pin 10 rises, up to tens of kHz. This charges a diode pump. The output at IC1.D pin 11 may then, if desired, be used to switch other logic circuits. The circuit's supply voltage may vary between 6V and 12V. Current consumption lies around 4mA. Best start with a small metal touch plate, say 5cm square. OBSERVATION: This circuit is a favourite of mine, for its stability and simplicity. The design is © Elektor. I have special permission to put it on my blog.

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About This Blog

I have spent ten years in suburban ministry, twenty-two years (total) in urban ministry, and seven years in country ministry. My involvements in ministry continue, now reduced.

There are a few reasons for this blog: 1. To help people form a picture of what ministry is about -- in particular urban ministry -- not least seminary students who may be destined for urban ministry. I have found that the image and the reality may be far apart in academia. 2. My experience in ministry may be (and, in fact, often has been) an encouragement to other ministers -- alternatively, a cautionary tale, as the case may be! Many notes of thanks have been recorded on this blog. And 3. Friends have simply told me how interesting reports of ministry are.

This is not a "parochial" blog. Only a tenth or so of readers are local (in South Africa). Outside of my home country, this blog is most read in Europe and North America. Russia is no. 4 on the list, and there is some interest in Muslim nations. At one point, this was the most authoritative Religion blog in Southern Africa (I now do not know how it is ranked).

With all of the above in mind, the purpose of this blog is simply to record urban ministry "live and unplugged", in the form of accounts. This blog is not a "church blog", but a "ministry blog". For the most part, I don't intend to share my views. The emphasis is the experience of ministry and the various events that surround it.

A definition of “live” is “actually being performed at the time of viewing”. A definition of “unplugged” is “without amplification or modification”. However, see my Posting Policy below.

Posting Policy

This blog may be unique with regard to its degree of transparency about urban ministry. Many people have written to me to say how they cherish the help they have received through this. However, this means that special attention needs to be given to confidentiality in particular. I use the following guidelines for posting on this blog:

I apply the following questions to posts: Are they posted in good faith? Are they balanced? Are they compassionate? Are they informative about ministry? Do they help one better understand a problem or issue?

I consider a post to be unproblematic if a person's identity is unknowable in the post, if the facts are public knowledge, or if a change of particulars (name, place, date, and so on) will truly protect privacy. If I consider that anyone who was not involved in an incident would recognise those who were, then I do not post. If a post could compromise the safety of those I blog about, then I make a post safe, or I do not post.

I believe that these measures should enable me to continue to be "open" about urban ministry while not compromising privacy.

In 2013, ninety percent of the posts on this blog were removed. I then put the question of the freedom of the blog to the South African Human Rights Commission. The position is this: if a post is legal, it is legal. Essentially, all of my posts were OK. There is freedom of expression in South Africa.

Having said this, if any post should even cause discomfort, it will be removed from this blog immediately. This has always been the position. One does need to contact me for that, best through an e-mail or a blog comment, and I prefer to see a name on it. The post will be put back up only if there would seem to be compelling reason for it. It is hoped that there will be the assumption that I wish to address any discomfort satisfactorily, compassionately, and efficiently.