This app was mentioned in 7 comments, with an average of 2.29 upvotes
First tip: try out ICalc and go to the hack page. It'll tell you how many hacks and hacking interval you get based on your mods.
It'll tell you that with 3hsvr and 1mhvr you get 16 hacks, each at 38 seconds interval and you'll burnout the portal in 9 minutes 30 seconds. So that's the ideal modding to maximize the Fracker time of effect. However, if you glyph, you'll probably still have a hack or two outside the fracker, since you spend more than a few seconds on each hack while seing the sequence then replicating it.
So probably the best idea in a real life scenario is to have 2mhvr and 2hsvr for a total of 22 hacks at 58 seconds interval. This will give you 9 fracked hacks and 13 unfracked.
Has to do with resonators and mods. This link took a L8 portal, 3x VRLA and 1x SBULA. A low level player could throw it if other players built the portal and the low level player had the key.
Below I've linked a calculator app that (among other functions) lets you enter portal builds and it tells you range, or enter distance and it tells you portal builds. Play with it!
https://play.google.com/store/apps/details?id=com.jwillis.icalcingresscalculator
This app works pretty well for that kind of stuff.
https://play.google.com/store/apps/details?id=com.jwillis.icalcingresscalculator&hl=en
https://itunes.apple.com/us/app/icalc-calculator-for-ingress/id1002962250?mt=8
There's an android app called iCalc that allows you to put in portal reso and mod details and it will calculate how far you can link with that setup.
Diminishing returns is the same for all 3 types of link amps. First mod is 1x, second is 0.5x, third is 0.25x, and the fourth is 0.25x.
One that hasn't been mentioned
ICalc - Ingress Calculator
Android https://play.google.com/store/apps/details?id=com.jwillis.icalcingresscalculator&hl=en
Apple https://itunes.apple.com/us/app/icalc-calculator-for-ingress/id1002962250?mt=8
Grab this app from the Play store... Dev is a good friend and this app won't let you down..
https://play.google.com/store/apps/details?id=com.jwillis.icalcingresscalculator
ICalc...never leave home without it.
https://play.google.com/store/apps/details?id=com.jwillis.icalcingresscalculator