Just for Fun - Hallowe'en 2009

HAPPY HOLIDAYS!!!!!

Created by Rick Maccani, our Technical Services Manager - with help from his wife.

For those of you who are "electronically challenged" the symbols are - - eyes=diodes, nose= capacitor, mouth equals resistor.

Special Modifications

Rapid Increase, Slow Decrease

("Peak Picker")

We've done this for a few customers. The basic application - monitor the peak value of a repetitive signal.
The first application was on an automated machine which formed nail heads. We never saw the machine, but our understanding is that it would "whack" heads on the nails in rapid succession. The user needed to know and control the impact force - not each and every individual impact, but the "normal" or "average" impact. In other words, he needed to know that the machine was properly set.
As the sketch shows, the output rises quickly to the peak value but decays slowly. (Actually, the unit we built had more filtering than is shown in the illustration.) The output of our module smoothed and held the value of the peak impact force.
We've built a few variations on this theme. One had an adjustable decay time (reference - our special feature #X0098) and one had a fixed 3-second time constant (X0214). Right now we're quoting a unit which adds a polarity-insensitive "absolute value" function - both positive and negative peaks will produce a positive output.

Links: Custom & Special Signal Conditioners
Our complete signal conditioner line

Special Modifications

Slow Increase, Rapid Decrease

Just the opposite of the "peak picker".

Application - Heating oven control.
The customer wanted to avoid rapid temperature increases and overheating and so wanted a "slow" filter on the control input. On the other hand, he required a rapid turn-off for fast shutdown. We were able to modify our transmitter's input stage to accomplish this.
(Reference - our special feature #X0251.)

Links: Special & Custom Signal Conditioners
Our complete signal conditioner line

New Product - Pulse Amplifiers

New Product

Announcement -

Low-Cost

Pulse Amplifiers

We've added two new pulse amplifiers to our product line.

For tachometers, turbine flowmeters and other magnetic coil pickups: Model JH376.

Two channels in one 0.7 in wide case. Each output is jumper-selectable, either 5V pulses or open collector. Highly sensitive, but includes sensitivity adjustments to optimize performance in noisy environments.

To convert logic pulses: Model JH377.

Inputs are jumper-selectable, either 5V/TTL or open-collector/contact closure. Outputs are jumper-selectable, either 5V pulses or open-collector. Again, two channels in one case.

Both products operate from 7 to 24Vdc power and at temperatures from -40 to +80 degrees C (-40 to 176 deg. F).

Links: Pulse Amplifiers and related products
All JH Technology Signal Conditioners

Absolute Value Function

Absolute Value -

with a difference

(Details on the application mentioned in our September 27 posting.)

A new customer had an urgent need for a signal conditioner (transmitter) with absolute value response. Searching the internet, he read our "Specials & Customs" page and found that we had done this before. His need was different, but we were able to help him.

For those of you who may not be familiar with the absolute value function, it simply ignores the minus sign. The previous special which he found on our web site took a -10 to +10 volt input and created a proportional 0 to +10V output. For example, inputs of either minus 7V or plus 7V created a plus 7V output.

The new customer's application needed a signal representing the temperature deviation from ideal. Ideal temperature produced a 12mA current signal. A deviation, whether positive or negative, required a positive-going output (see graph). At 12mA input the output should be zero percent (4mA). At either 4mA and 20mA (8mA deviation) the output should be 20mA (100%).

We were able to modify the earlier special to accomplish this. As mentioned in our Sept. 27, 2009 post we did some Thursday evening calculations, quoted and took the order on Friday, built 6 units on Saturday (yes - we added an expediting charge) and shipped Monday.

Let us know what we can do for you!

Links: Custom & Special Signal Conditioners
Our home page: http://www.jhtechnology.com/