Lafayette HE-10 Communications Receiver
Operating Manual
Lafayette Radio Store Locations
The Lafayette HE-10 Communications Receiver is available through Lafayette Radio stores:
- New York, NY: 100 6th Ave.
- Boston, MA: 110 Federal St.
- Bronx, NY: 542 E. Fordham Rd.
- New York City, NY: 165-08 Liberty Avenue, Jamaica 33, NY
- Newark, NJ: 24 Central Ave.
- Plainfield, NJ: 139 W. 2nd St.
Specifications
| Feature | Specification |
|---|---|
| Speaker Output | 4, 8 ohms |
| Headphone Output | High Impedance |
| Antenna Input | 300 ohm balanced line or 75 ohm unbalanced line |
| Power Output | 1.5 watts |
| Power Source | 105-125 volts, 50-60 cycles AC |
| Power Consumption | 50 watts |
| Tuning Range | 550 KC to 30 MC in four bands |
| Intermediate Frequency | 455 KC |
| Sensitivity | 1.25 μv for 10 db S/N ratio |
| Selectivity | -60 db (at 1 MC ± 10 KC) |
| Size | 7-7/8"H x 15"W x 9"D |
| Weight | 20 lbs. |
| Tubes | 1-6BD6 RF Amplifier, 1-6BE6 Mixer, 2-6BD6 1st and 2nd IF Amplifier, 1-6AV6 Detector, AVC & AF Amplifier, 1-6BE6 BFO & ANL, 1-6AR5 Audio Output, 1-5Y3GT Full-Wave Rectifier |
Unpacking Instructions
Upon unpacking the receiver, check for any damage incurred during transit. If damage is apparent, file a claim with the carrier immediately. The following accessories should be included:
- 80" Speaker lead
- 1 Standard Phone Plug
- 1 Plug (for the Auxiliary Control Socket)
General Description
The Lafayette HE-10 is a high-quality superheterodyne communications receiver covering frequencies from 550 kilocycles (KC) to 30 megacycles (MC) across four bands. It utilizes nine tubes, including a full-wave rectifier, and supports both AM and CW (code) reception. The receiver is powered by a 105-125 volt AC, 50-60 cycle source and is capable of driving a 4-12" PM speaker.
Key features include bandspread tuning for fine adjustment on shortwave bands, an automatic noise limiter (ANL) to reduce interference, a front panel headphone jack, and controls for automatic volume control (AVC), beat frequency oscillator (BFO), and receive/standby functions.
Frequency Coverage
| Band | Frequency Range | Type |
|---|---|---|
| A | 550 - 1600 KC | Broadcast |
| B | 1.6 - 4.8 MC | SW |
| C | 4.8 - 14.5 MC | SW |
| D | 11 - 30 MC | SW |
Installation
Power Source
The receiver is designed for 105-125 volt, 50-60 cycle AC power. Power consumption is 50 watts. Do not operate from a DC source, as this may cause serious damage.
Speaker Connection
A three-terminal OUTPUT strip at the rear is provided for speaker connections. Any PM speaker with 4 or 8 ohm impedance can be used. Connect one lead to the ground terminal "O" and the other to the terminal matching the speaker impedance. The receiver's output power is sufficient for a 4-12" PM speaker.
Headphones
A standard phone jack on the front panel allows headphone reception. High impedance headphones are recommended for maximum output. Commercial high impedance crystal or magnetic headphones may be used. Inserting a phone plug automatically disconnects the speaker.
Antennas
Antenna and ground connections are made via terminals "A1", "A2", and "E" at the rear. Two common antenna types are recommended:
Inverted L Antenna
This antenna type provides satisfactory performance across the tuning range. To set up, short terminals "A2" and "E" with a jumper wire, and connect the antenna wire to "A1". For best results, the antenna wire should be as high as possible and 50-100 feet long. Connecting terminal "E" to a water pipe may also improve reception.
Doublet Antenna
A doublet antenna is recommended for excellent results, particularly on amateur bands. A 300-ohm balanced transmission line (like "TV twin lead") can be used. The optimal length for a doublet antenna is determined by the frequency band it will be used for, using the formula: L (Length in feet) = 468 / Frequency (in megacycles). The antenna should be oriented for maximum signal pickup, with its length broadside to the signal source. Connect the transmission line leads to terminals "A1" and "A2", removing the jumper between "A2" and "E". A height of 30-50 feet is recommended for weak signal reception.
Fuse
A 1-amp fuse is located at the rear of the receiver, accessible by unscrewing the spring-loaded cap.
Operation
Familiarize yourself with the following controls for optimal receiver performance:
- AF GAIN: Acts as the receiver on/off switch and volume control. Clockwise rotation turns the receiver on and increases volume; counter-clockwise rotation decreases volume and turns it off. Dial illumination indicates the receiver is active.
- BAND SEL: Select the band corresponding to the desired frequency range.
- RECEIVE/STAND BY: Switches between active reception and standby mode. In standby, RF stages are powered down but heaters remain on, allowing for instant return to reception.
- Auxiliary Control: A 5-pin socket on the rear allows simultaneous control with a transmitter. An external switch can connect pins (3) and (2) to enable/disable reception, allowing for instantaneous signal reception by applying plate voltage to RF stages when the switch is closed.
- ANL ON/OFF: The Automatic Noise Limiter switch. Engage this if excessive spurious noises (e.g., from auto ignition) interfere with reception. It may reduce overall receiver efficiency and should be used only when necessary.
- MAIN TUNING: Operates the main tuning dial, which features four calibrated frequency scales for different bands. A 100-division logging scale aids in logging stations.
- BANDSPREAD TUNING: Electrically spreads out the main tuning dial scales, particularly useful for separating closely spaced shortwave stations. Setting the bandspread pointer to '0' aligns the main tuning scale. Moving the pointer towards '100' subtracts from the main tuning frequency.
- BFO PITCH: Adjusts the audio tone for CW signals. Set to a pleasing pitch. This control is active only when the BFO-MVC-AVC switch is in the BFO position.
- BFO-MVC-AVC Switch:
- AVC: Activates the Automatic Volume Control circuit, compensating for fading and maintaining constant output.
- MVC: Disables the AVC circuit, useful when a weak station is adjacent to a powerful one, or for added gain on weak signals. Not recommended for strong signals to avoid overloading and distortion.
- BFO: Activates the Beat Frequency Oscillator for intelligible CW reception, used with the BFO PITCH control.
- IF GAIN: Used with AF GAIN to regulate output during CW reception. Reduce sensitivity by turning counter-clockwise if overloading or distortion occurs with strong signals.
- S METER: Measures incoming AM signal strength. Operates only when the BFO-MVC-AVC switch is in the AVC position. Features an "S METER ADJUST" control for calibration. To calibrate, remove the antenna, set IF GAIN to maximum, and adjust "S METER ADJUST" for a '0' reading. Reduce IF gain if necessary for very powerful stations to prevent high meter readings.
Diagram Description: The Auxiliary Control Socket (Figure C) is a 5-pin socket located on the rear of the receiver. It allows external switching control, typically with a transmitter. Pins (3) and (2) are shown connected to an external switch, enabling the receiver's operation.
Short-Wave Listening
Bands B, C, and D cover shortwave frequencies, offering access to global broadcasts and amateur radio transmissions. Reception quality can vary with time of day, season, and weather conditions. The manual includes a listening chart for English-language broadcast stations best heard in North America and references The Amateur's Radio Handbook for amateur frequency bands.
Tuning the Receiver
AM Reception
Set the Band Selector to the desired frequency band. Set the BFO-MVC-AVC switch to AVC, IF GAIN to maximum, and AF GAIN for a comfortable listening level. Set the Bandspread pointer to "0". Tune the desired station using the Main Tuning control. For fine-tuning, adjust the Bandspread control clockwise if the station is slightly higher in frequency. Use the ANL switch for noisy conditions. If the station is weak, switch to MVC for added gain. If overloading occurs, reduce IF GAIN or switch back to AVC.
CW Reception
Set the Band Selector to the desired frequency band. Set the BFO-MVC-AVC switch to BFO, IF GAIN to approximately midway, and AF GAIN for a comfortable listening level. Tune in to a CW signal and adjust the BFO PITCH control for a pleasing tone. Use the Main Tuning control to tune the station with Bandspread at "0". For fine-tuning, adjust the Bandspread control clockwise. Readjust BFO PITCH for tone and use ANL for noise reduction. Adjust IF GAIN for suitable level to prevent overloading.
Note: Always set IF GAIN as high as possible without causing overload or distortion.
Service
The receiver uses high-quality parts for longevity, requiring minimal service beyond occasional tube replacement. A schematic diagram is provided for servicing, including expected voltage measurements (±20% variation is normal). For repairs, the unit can be returned to the service department. Warranty repairs are free if conditions are met; otherwise, charges apply for parts and labor. When returning the receiver, include a letter detailing the difficulties encountered. Pack the unit carefully in its original carton with spacers, or a sturdy carton with at least 3 inches of protective material, ensuring no packing material gets inside the unit. Ship via prepaid express and mark as FRAGILE.
Diagram Description: Page 6 displays the schematic diagram for the HE-10 receiver, illustrating the internal electronic components and their interconnections, intended for service and troubleshooting purposes.
Short-Wave Broadcast Station Listings
Pages 7 and 8 of the manual provide extensive lists of English-language short-wave broadcast stations that are best heard in Western North America. These listings are organized by Pacific Standard Time (PST) and include the City and Country of origin, the station's name or service identifier, and the frequencies (in kilocycles) used for their broadcasts. The lists cover various regions and times, aiding listeners in finding international broadcasts.
