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Pre-tin the solder leads on the new SSB filters with just a little solder, so it will make soldering in the tight area much easier, when they are installed.

Start with the “upper’ sideband filter first (left filter bottom up), from the top of the radio.
Put on the nuts and use the small screwdriver and long needle-nose pliers to tighten the nuts up good, (do not tighten the bottom nuts yet). Solder the wires that were taken off before.
Install the “lower’ sideband filter now the same way.
Re-install the CW/AM filter mounting plate, tighten the nuts on the bottom of the filters to hold the plate tight.

Your all done with the installation, now I would go and align the 9 MHZ carrier oscillator (C-130), along with the filter matching transformers T-6 and T-13, null out the transmit carrier also on 80 meters in USB mode, as per the manual.

I have compared this TR-4CW with the other one I have on receive and transmit, although the audio on the INRAD radio does sound a bit more mellow, do to the fact these filters are 2500 HZ wide compared to 2100 HZ on the stock filters. I’ve had good audio reports using the INRAD filters, so I can say they work great!

The model number of the filters are: 1901=USB and 1902=LSB. The cost of the filters are $110ea. from INRAD, the phone number is: (541) 459-5623 or qth.com/INRAD, e-mail is: inrad@rosenet.net. Let’s keep the old TR-4’s going!

73……..Jeff Covelli/WA8SAJ