At the meeting yesterday I suggested that the novae that Eliot Merlin had viewed with a spectroscope over a hundred years ago could still be recorded spectroscopically today despite being some 13 magnitudes fainter. The two novae that Merlin is known to have observed are Nova Aql 1918 and Nova Gem 1912. (J. Br. Astron. Assoc. 127, 1, 2017 page 30)
The former at around mag 12 is straightforward for the ALPY 600
https://britastro.org/node/14188
but the latter is much more of a challenge. (SIMBAD lists it at mag 15 but it looked more like mag 16 from my guider image)
In fact it took a total of 9 hours exposure with the ALPY 600, spread over three, admittedly not the most transparent of nights to pull out the rather weak emission lines out of the noise.
A rough estimate of the line strengths suggest they are similar to those from Jan 2000 reported in this paper
https://iopscience.iop.org/article/10.1086/504641
Robin