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Chirs you will likely get a hundred different answers. I had a FRG-7 that was deaf. It turned?out to be coil L101. This is a large multi segmented coil. The problem was the ends of the coil are wire wrapped into the circuit. Even though the wire wrapped posts looked sound it failed electrically. I had to clean the connection with flux multiple times and then solder it in place. Radio works fine now.

Do you have the manual with the alignment instructions? You need that and a nanoVNA and tinySA or two. The 2nd is for use as a signal generator. Connect CH0 of the nanoVNA to the antenna input attach a probe to CH1 and start tracing your way thru the radio doing the alignment. You'll either find or fix the fault in the process. At some point results won't match the instructions.

Key traits:

manual preselector
Barlow-Wadley loop circuit
use of harmonics of 1 MHz oscillator to change frequencies

A good white noise source (NOT a BG7TBL!!!) will let you check the performance of the preselector with a tinySA. In fact, if budget is tight a tinySA and white noise source will do everything you need for under $100. A search on EEVblog for user rhb should find comparisons of the two noise sources.

The one of this pattern

https://www.ebay.com/itm/265453613573

that I have tested is quite flat to 1 GHz and then starts to roll of. Over the narrow spans and frequencies you need to use it will be perfectly flat. I've posted 8560A screen shots of the performance. The noise source should have a 2nd voltage regulator as the MIMICs are being fed unregulated input power and it's particular about what you feed it. I plan to add a LiPo and charger.

My FRG-7 is on loan at the moment. It was the first radio I ever did an alignment on for the simple reason I didn't have the needed instruments. I very much enjoyed it. I redid it a 2nd time just to be sure I had it right and to catch any potential coupling problems between stages. Just make sure you have the correct adjusting tools as you don't want to damage a tuning slug.

Basic procedure outline

check the operation of the preselector with the noise source. You should see the peak back and forth on the SA. and it should be of uniform amplitude at the preselector output. Then check at the mixer input to see the signal amplitude is constant check the LO input to the mixer and the output. Then align the harmonic oscillator chain. Use a magnifying glass and check for craks or solder flux residue.

If you observe cracking or corrosion I recommend fluxing the entire board and reflowing it with a hot air gun. If there's one you, see there are many you don't.

Have Fun!
Reg

The fault lays in the Wadley loop section .

You need to ascertain the Mhz VFO is working, this runs from 55 mHz to 85 mHz.

Because your lock light goes out at the higher frequencies, this oscillator seems to be working fine.

The loop amplifiers then need to be checked, this can be done without any test equipment to get you in the ballpark..

Reduce the mHz tuning until the lock light begins to extinguish, and while watching its brilliance, carefully and SLOWLY adjust each coil slug looking for a greater dip in brilliance. The lock LED monitors the RF output amplitude? of the loop amplifier chain and is a very good indicator of output level.

? As this improves, tune further down in mHz frequency and repeat the adjustments until no further improvement. This applies to T109 through to T116. Do not fiddle with anything else, although this radio has quite possibly been a victim of the golden screwdriver.

IF the band pass alignment was the issue, the radio will now receive signals.

The main mHz tuning can next be aligned, also without any test equipment.

Tuning in a known BC AM signal, the slug on the VHF VCO can be adjusted to bring the mHz tuning drum into alignment, and then tuning into a known signal in say, the CB band on 27 mHz, the trimmer capacitor can be adjusted to align the 27 mHz frequency to the correct dial setting.

Once done, the signal BPF and third IF filters can be simply peaked on signal.