Simple resistive load

This is simple resistive load,Sometimes we need to use a resistors that without capacitance or inductance. We always use the carbon resistors. But some working to need the resistor that has also many high power. Which we cannot use the carbon resistor because it has maximum power about 2 watts only.

Normally, performance testing of amplifiers need to apply low resistance load and not affect the frequency. That is pure resistance requirements and The normally power amplifiers have also have high power. (Several hundred watts)

Alternative way is to change the resistor into the wire wound model. This resistor tolerance is very high. Because structure is a wire with a high resistance on the ceramic core. The problem is the inductance hidden inside. Which is caused by winding wire is coiled itself.

Figure 1 Simple resistive load

If as the DC circuit this lower inductance, no problem. But for working with high-frequency circuit will result in a lot.

The solution is connects the circuit as Figure 1. The current flow in resistor will opposite and cancel out. However, the total resistance has been reduced from the original. Assuming the value of R, but was divided into two parts. Each section is equal to R / 2 and when the two parts are connected in parallel and be left with impedance R / 4.

This resistor can connects to point out the resistor is (tap). Which currently may be hard to find. But there is another way Using conventional 2-wire resistor with a resistance equal to the parallel instead. But do not forget to consider the resistance forces and the resistance of the circuit is required.

Make Lamp as power load

We like to test the functionality of a high current power supply by simple power load. It is 12V lamp 50 watts. But it had a high temperature. Require a docking station proper on long time trials.

Today my son build docking for this lamp.
001_All parts
Figure 1 All parts
We use:
– Light bulb
– Metal screw 2 inch
– brass hooks as terminals
– Thick wooden planks

We use Incandescent motorcycle head light bulbs 12V 25W/25W without a head light socket

002_The structure inside light bulb
Figure 2 The structure inside light bulb

The structure inside light bulb has two filaments for the high beam and low beam filaments are soldered two parallel, it would have a combined 50 watts as Figure 3.

003_Both Filament are soldered together
Figure 3 Both Filament are soldered together

Then, install screws and the brass hooks on planks as Figure 4
004_brass hooks on planks

Figure 5; We install the screws and the brass hooks onto the planks are finished.

It is technically simple electronic If you are experiencing similar problems. Get lucky.

Sharing is caring!

JLCPCB - Only $2 for PCB Protytpe(Any Color)

With 600,000+ Customers Worldwide, 10,000+ PCB Orders Per Day

Up to $20 shipping discount on first order now:

Related Posts


I always try to make Electronics Learning Easy.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

newest oldest most voted
Notify of
Salim Khan


MR OHM 1970

And Very Useful!!!!

Close Menu