The Pioneer TX-7800 is one of those late-'70s FM tuners that earns its place in a system through quiet competence rather than fanfare. Part of Pioneer's Blue Line series and a sibling to the more celebrated TX-9800, it brings the same remarkable station-pulling ability in a slightly more accessible package — latching onto distant signals with real authority and holding them rock-solid via the varicap servo-lock circuit, just as promised. The FM presentation is clean and well-separated, with a naturalness to voices and acoustic instruments that not every solid-state tuner of the era manages. The selectable AM bandwidth is a genuinely useful and rare touch. One of the more quietly accomplished tuners Pioneer ever made — and one that rewards a proper service.
Production
1979-1981
Condition
9/10
Serial No.
AK2902417M
Orig. MSRP
$350
Restoration
- New power indicator light
- Cleaned all controls
- Thoroughly detailed
Factory Specs
Tuning Range 87.5 – 108 MHz
Usable Sensitivity (Mono) 9.3 dBf (1.6 µV)
50 dB Quieting Sensitivity — Mono 15.5 dBf (3.3 µV)
50 dB Quieting Sensitivity — Stereo 37.1 dBf (39.2 µV)
Signal-to-Noise Ratio — Mono 83 dB
Signal-to-Noise Ratio — Stereo 79 dB
THD at 85 dBf — 100 Hz (Mono / Stereo) 0.08% / 0.1%
THD at 85 dBf — 1 kHz (Mono / Stereo) 0.05% / 0.08%
THD at 85 dBf — 10 kHz (Mono / Stereo) 0.06% / 0.3%
Frequency Response 20 Hz – 15 kHz, +0.2 dB / -0.5 dB
Capture Ratio 1.0 dB
Alternate Channel Selectivity 75 dB
Stereo Separation 50 dB at 1 kHz; 35 dB (20 Hz – 10 kHz)
Spurious Response Ratio 95 dB
Image Response Ratio 85 dB
IF Response Ratio 100 dB
AM Suppression Ratio 65 dB
Muting Threshold 19.2 dBf (5.0 µV)
Subcarrier Ratio 70 dB
Antenna Input Impedance 300 Ω balanced; 75 Ω unbalanced
De-Emphasis Switch 25 µs / 50 µs / 75 µs switchable (S and S/G models only)
Tuning Range 535 – 1605 kHz
Sensitivity — IHF Ferrite Antenna 300 µV/m
Sensitivity — IHF External Antenna 15 µV
Selectivity — Wide 15 dB
Selectivity — Narrow 50 dB
Signal-to-Noise Ratio 50 dB
Image Response Ratio 45 dB
IF Response Ratio 50 dB
Antenna Built-in ferrite loopstick; external antenna terminal provided
Fixed Output — FM (100% mod.) 650 mV / 4.2 kΩ
Fixed Output — AM (30% mod.) 200 mV / 4.2 kΩ
Variable Output — FM (100% mod.) 0 mV to 1.3 V / 3.6 kΩ
Variable Output — AM (30% mod.) 0 mV to 400 mV / 3.6 kΩ
Complement 2 × FET, 7 × IC, 11 × Transistor, 30 × Diode
Power Supply AC 110 / 120 / 220 / 240 V, 50/60 Hz (voltage selector)
Power Consumption 23 W (S and S/G models); 20 W (HG model)
Dimensions 16-9/16 × 5-7/8 × 15-3/8 inches (W × H × D); S/G model with wooden cabinet: 17-13/16 × 6-1/8 × 15-3/8 inches
Weight 16.53 lbs (7.5 kg); S/G model: 18.30 lbs (8.3 kg)
Documentation
Pioneer TX-7800 Schematics
The History of Pioneer
Pioneer was founded by Nozomu Matsumoto in 1938 in Tokyo as a radio and speaker repair shop. In December 1953 Mr. Nozomu Matsumoto succeeded in developing the first domestic dynamic speaker made of original parts. It was named A-8 and marketed in Japan under the Pioneer brand. It later became the origin of the HiFi ...
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Liner Notes
Three important criteria were included in the design concept drafted by Pioneer for this attractively-priced stereo FM/AM tuner. First was high tuning accuracy — station-pulling capability in any reception circumstances is the least we can offer customers who look to us for state-of-the-art performance. Superior high fidelity tonal quality and improved tuning convenience were also on the list. Our engineers developed the unique Servo-Lock/Touch Sensor system featured here so that all three demands are fully met. Absolutely no changes of temperature, humidity or other environmental factors can cause the drift or de-tuning of an FM station once you have locked it in.
A low-noise, dual-gate type MOS FET is employed in the FM front end of the TX-7800. It has superior cross modulation characteristics responsible for the high sensitivity and high interference rejection capability in FM reception. The MOS FET works with an elaborate frequency-linear 4-gang variable capacitor and the Servo-Lock system to assure stable tuning accuracy at all times. In the FM IF section, two high-gain ICs are employed as differential-type IF amplifiers, deployed with no fewer than three phase-linear ceramic filters to further improve interference rejection characteristics — FM alternate channel selectivity, for example, is an excellent 75 dB.
The AM section incorporates a 2-gang variable capacitor tuned RF amplifier circuit and a highly sensitive, low-distortion IC. According to signal conditions, the AM IF amplifier can be selected for a wide-band (high fidelity) or narrow-band (high selectivity) mode, making AM listening more enjoyable by eliminating booms, whines and whistles for a cleaner sound.
Packing
Prepare to be impressed. We have arguably the best packing process around. We use our InstaPak machine and white open cell foam to build a custom enclosure for your piece that ensures that it's stable and secure. If it is particularly fragile or heavy, we typically opt for private courier delivery. Depending on where you are in the country, that may cost a bit extra.
Shipping
This piece ships to the contiguous United States for a flat rate of $75, which includes our packaging and our insurance. Of course, we'll ship anywhere in the world, just drop us a line and we'll give you an estimate – even if you're just curious.
Stock No.
9679539601629
