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(HP-67/97) Microstrip Impedance - Printable Version

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(HP-67/97) Microstrip Impedance - SlideRule - 10-16-2019 11:35 AM

An extract from microstrip impedance program, ham radio magazine, volume 17 number 12, December 1984 (pg. 84)

"Use your TRS-80, HP-41, or HP-67/97 to determine stripline width and other parameters …
Even though programmable calculators and computers can easily be used to perform microstrip impedance line calculations, I haven't seen many suitable programs in print.
The two synthesis programs listed here were written for use on the Radio Shack TRS-80TM computer (fig. 1) and the HP-67/97 or HP-41 (fig. 2). Both may be adapted for use on other programmable calculators and personal computers.
The programs allow the user to input a desired microstrip impedance value, frequency, relative dielectric constant and thickness to calculate the correct linewidth for that impedance. It will also output the effective dielectric constant, relative velocity factor, and 90-degree microstrip line length.
The mathematics used represent a good closed form approximation for line impedances between 20-110 ohms and will deliver results that fall within 3 percent of Wheeler's line impedance values …

fig. 2A. User instructions for microstrip impedance line program for HP-67/97 or HP-41 calculators …

fig. 2B. Program listing for microstrip impedance line program for HP-67/97 or HP41 calculators …"

BEST!
SlideRule


RE: (HP-67/97) Microstrip Impedance - jpcuzzourt - 10-17-2019 04:09 AM

(10-16-2019 11:35 AM)SlideRule Wrote:  Even though programmable calculators and computers can easily be used to perform microstrip impedance line calculations, I haven't seen many suitable programs in print.
The two synthesis programs listed here were written for use on the Radio Shack TRS-80TM computer (fig. 1) and the HP-67/97 or HP-41 (fig. 2). Both may be adapted for use on other programmable calculators and personal computers.

Thanks for posting.
My first programmable digital device was a TRS-80 CoCo. Neat to see program listings for both a TRS-80 and HP calculators in print from back in those days.