One of the finds from the 2022 Atlanta Hamfest that I’m most excited about is the bin of slide rules and slide rule books that Connie found at one of the flea market tables.
A bin of slide rules and slide rule books
There were 10 different slide rules and a total of 12 slide rules in the bin. Some of them were pretty basic slide rules, and some were more advanced with multiple scales, some of which I hadn’t seen before. These bring my slide rule collection up to 15.
I’ve made a first pass through the bin to check out the slide rules and jot down some notes about them. All of them are in pretty good condition, although one of them is missing the cursor. Two Keuffel & Esser rules, three Picketts, three Sterling, a couple very short pocket sized slide rules, and a little circular rule with some basic scales on it.
It will take me a while to research, photograph, and learn more about each slide rule. Should be a fun project.
I grew up with electronic calculators and while I remember my uncle having a slide rule that I played with as a kid (didn’t know what it was at the time…it was just a neat looking thing with slide-y bits and numbers printed on it), I never used one until I got my first one in high school.
One day, at the end of one of my high school math classes, I noticed the teacher using something that wasn’t a calculator to work out the grades on a test we just had. Intrigued, I went over and asked about it. He was using a slide rule, showed me some basic operations on it. He was calculating percentages faster on his slide rule than using a calculator. I thought it was just the neatest thing in the world. He reached into one of his desk drawers, pulled out a box, and handed it to me.
I had my first slide rule!
Ricoh No. 102 slide rule case
Ricoh No. 102 slide rule
It’s a pretty simple beginner’s slide rule made of bamboo with a plastic reticle. It’s a single sided slide rule with a reversible slider. that has B/CI/C scales on one side and S/L/T scales on the other. Seems like this model would have been an inexpensive slide rule targeted at the student market.
Ricoh No. 102 slide ruleA|B CI C|D K scales on the Ricoh No. 102 slide ruleA|S L T|D K scales on the Ricoh No. 102 slide rule
The back side has some handy reference tables and formulas.
Helpful references on the back of the Ricoh No. 102 slide ruleHelpful references on the back of the Ricoh No. 102 slide rule
I taught myself how to use a slide rule and used it pretty regularly through my last year of high school and into my first couple years of undergrad. The main reason I stopped using it was that most of the problems became more symbolic, and the numeric problems I did get became complex enough that it was faster for me to use my calculator (HP-28S at the time). The slide rule stayed in the desk drawer for the rest of my undergrad and grad school.
Most of my calculations are done using spreadsheets now, but I pull the slide rule out every now and then for some quick calculations and to remind myself how to use it.
Acquired some slide rules this week (that makes three that I have now, so I think that qualifies as a collection). The new additions came from the estate of N6GA (SK) and were posted on one the amateur radio mailing lists I subscribe to. Both came in hard cases and are in pretty good condition.
Keuffel & Esser (K&E) 4080-3 log-log slide rule (top) and Pickett N-515-T Cleveland Institute of Electronics electronics slide rule (bottom)
The plastic brace parts of the reticle are broken, and there’s some corrosion on the metal frame. Think it might be possible to fashion some replacement braces out of bamboo or something similar. Looks like I might be able to purchase a used one too. No manual for this one, so I’ll have to see if I can hunt one down.
Pickett N-515-T Cleveland Institute of Electronics Electronics slide rulePickett N-515-T Cleveland Institute of Electronics Electronics slide rulePickett N-515-T Cleveland Institute of Electronics Electronics slide rulePickett N-515-T Cleveland Institute of Electronics Electronics slide rulePickett N-515-T Cleveland Institute of Electronics Electronics slide rulePickett N-515-T Cleveland Institute of Electronics Electronics slide rulePickett N-515-T Cleveland Institute of Electronics Electronics slide rulePickett N-515-T Cleveland Institute of Electronics Electronics slide rule
Will be fun learning how to use these slide rules.
