Hi Gang....I have a T4X-C that has a damaged C-17 1-8 pf cap used in the balanced modulator in conjunction with R-21 200 ohm to null the carrier. My C-17 looks like the white plastic tube has been heat shrunk.....anyway, I can't fix it. If anyone has a C-17 from a T4X-C or C-127 from a TR-4XX I would appreciate an email. The above part numbers seem to be the same part 1-8pf. Thanks Dave K6XYZ