- 13 March 2007 : First Edition
Resistors are usually manufactured according to a specific set of resistance values. Two common value sets are the E24 set of values and the E96 set of values. While it is possible to find resistors manufactured to a wider set of values, it may involve a custom order and need a longer lead time.
Placing two resistors in series or parallel using the more common set of values is one way to create a resistance value closer to the desired value.
This program can help in the selection process: by selecting the desired target value, the allowed error in percentage, and the connection type, the program lists the combinations which are within these parameters.
- Series or parallel selection.
- Use E24 or E24+E96 series values.
- Adjustable error allowance 0% to 10%
- Import a list of target values for batch mode use.
- Results are listed in a scrollable window.
- Date and time and software version listed in window.
- Select for copy/paste operations supported.
- Window results can be written to a log file.
- Resistor power is listed for a given voltage.
- A single win32 executable. Does not install or require any libraries or updates.
Figure 1 Rombo Screenshot
- more intelligent combination searches, especially for E96 searches. A search of a high resistance values can produce several combinations like 100000 and 10, 100000 and 12 , etc.
- for parallel mode, an open is listed as 9999999. Could be done better.
- settable decade ranges. Would be especially useful to do this for E24 and E96 separately.
- importing a custom set of available resistor values could be useful to do the search
- listing all the actual resistor values used in the program would be good practice.
- add aging and manufacturing tolerance calculations.
- a Linux version if demand is there. GUI is FLTK based.