The tenor banjo is seeing a revival of sorts. Traditionally tuned in intervals of 5ths (C, G, D, A - standard tuning, G, D, A, E - Irish tenor tuning), many guitar players are taking up the tenor banjo today and are tuning their tenors to Chicago tuning.
Chicago tuning is a type of tuning traditionally used for 4 string plectrum banjos that is tuned the same as the top 4 strings of a guitar (D, G, B, E). This allows guitarists to use the same fingerings as they do on guitar. This tuning is traditionally used on plectrum banjos because the scale of the neck of plectrum banjos is very close to that of guitars so standard plectrum banjo strings can be used.
For sure, many guitarists are doing this with tenor banjos as well. There is an issue though if a standard set of tenor banjo strings is used (standard tuning or Irish tuning sets), specifically with the 1st string and 4th string.
Changing the 1st string from a high A string (standard tenor tuning set) to an E (Chicago tuning) is a pretty big change. You are going to need a heavier gauge string to make up for the lack of string tension. The same goes for the 4th string if you are using an Irish tuning set. The 4th string in Irish tuning is a G. In Chicago tuning it is a D. Again, that is too big of a change. This time the Irish set has too heavy of a string and you need a lighter gauge string.
What I recommend is using half a standard tenor set for the 3rd and 4th strings, and the strings for the 1st and 2nd strings from an Irish tenor tuning set. This is because in standard tuning the 4th string is tuned to a C. In Chicago tuning it is a D. That is very close. In standard tuning the 3rd string is tuned to a G which is the same as Chicago tuning, so that string works.
Now we have to switch to the Irish set for the 2nd and 1st string because in Irish tuning the 2nd string is tuned to an A. In Chicago tuning it is tuned to a B - so that is close enough. Lastly the 1st string in Irish tuning is tuned to an E which is the same as Chicago tuning, so this string works.
Suggested gauges are as follows:
1st string: 12
2nd string: 18w
3rd string: 24w
4th string: 30w
So, if you are predominantly a guitar player and you are looking to get into banjo, the tenor is a great alternative to the popular 5 string instrument.