Read the AIG FM Tuner Project Introduction

This TX-7800 is the last of the Pioneers, so to speak, unless I’m tempted into another one, say, an F-26 or 28. But they’re expensive, and not seen very often, held tight to the breast by captivated owners! The TX-7800 is, admittedly, somewhat less rare, but but definitely has its fans. Looking at the front panel’s left side, we see the Power toggle, and toward center the replaced Output Level control, which I chose from my knob box to as closely as possible match the tuner’s style. The original was missing at purchase. The meters are above on the dial’s left end. The large Tuning knob is just right of center, and tuning action is very smooth and flywheel facilitated, like that on all Pioneer analog tuners. To the right are 4 toggles marked Function (FM/AM), AM IF Band (Narrow/Wide), Multiplex Noise Filter (On/Off), and FM Muting/Mode (Auto Stereo/Mute or Mono/Mute Off).

At left rear we see the antenna inputs, all finger screw taps except the Philips-screw 75-ohm ones, which accept bare stripped coax cable. The AM antenna is at center, and in perfect condition, rotating both vertically and horizontally, also underlining the excellent AM tuner section. Below it are both Fixed and Variable RCA audio outs, along with Vertical and Horizontal scope RCAs. There’s also an AC outlet at extreme right. Our sample comes with a complete Service Manual on CD.

In our reception tests, the TX-7800 brought in 41 stations on our outdoor directional Yagi, and 48 stations on the double dipole omni antenna. In the latter case, there were more listenable stereo signals, showing a clear preference for the 300-ohm input, not uncommon in tuners of this era, the late 70s. The dial calibration was just slightly offset (200 kHz or less) to the right, but this is easily fixed. It’s a very nice sounding tuner, with the open quality of the TX-9500, as well as the excellent bass and a nice sweet top end. Not quite an Accuphase T-101, but there it is…

Our experience with weaker stations was perhaps not quite as enthusiastic as the fmtunerinfo tester quoted below, but not only do opinions vary, but also reception conditions. Here’s what they say about the TX-7800:

“This little brother of the TX-9800 has 4 gangs and 3 filters, like the Kenwood KT-7300, but its performance is stunning: more sensitive than a modified Onkyo T-9090, and just about as selective as the T-9090 when modified with one 110 kHz and two 150 kHz filters.”

“But a modified TX-7800 might be superior to a modified [Kenwood] KT-7500 for DXing, with terrific adjacent channel rejection and a crisp, clean sound. It does, however, have an annoying combined “Muting On/Stereo” and “Muting Off/Mono” switch that prevents one from choosing to listen to a weak signal in slightly noisy stereo.”

This TX-7800 is in excellent cosmetic condition, with one small scratch near the top right front panel edge, which could be buffed away, I think. All dial lights and indicators work perfectly. The wood case is unscratched, but is covered in a very realistic walnut vinyl which has started to peel with age. I did a little work with a glue stick at several corners, but you could easily cleanly peel it all off, and replace it with your own adhesive covering choice. I thought a nice warm brown leatherette would be nice. This Pioneer TX-7800 could be a project as well as a prize! It has, however, been aligned by All-In-One Electronics in Toronto, and should provide excellent reception right out of the box.

Andrew Marshall