BHI NES-5 Bedienungsanleitung

THE DRAKE TR7 RENEWED By: DL/PA1HFO - Marc van Stralen Date: 08/19/07 The TR7 is still a remarkably good transceiver compared

SPEECH PROCESSOR The speech processor is a design of DK4SX who used it for his modified TR7. The processor is based on the SSM2166 IC from Analog De

TR7 SPEECH PROCESSOR PCB

Component Layout Speech Processor PCB Solder Side Speech Processor PCB Scale 1:1 Parts List Sprachpr

Ref. Desinator(s) Qty Description Grid R1 1 10 K Widerstand, Resistor 1/8 watt, R2 1 10 K Widerstand, Resistor 1/8 watt, R3 1 1

C22 1 22 µF/16V Rad. 1 E C23 1 10 nf Kondensator, Capacitor/ Keramisch, Ceramic 1 E Ref. Desinator(s) Qty Description Grid U1 1 4066

The 100 Hz digit of digital read out of the TR7 I used for this renovation was not 100 % any more. So I had to replace the complete LED assembly by

The second change is to replace the two rear mounting screws of the power amplifier unit with longer ones. The longer screws will be used now to fix o

SPACERS FOR THE SIDE PANELS To assemble the two side panels to the transceiver four spacer strip are made of 4.3mm thick aluminium or brass.

TOP AND BOTTON COVER PLATES A top plate and bottom plate are made from 1.5mm aluminium and adequate holes are drilled for the necessary ventilation.

KEY JACK A small 3mm phone jack is being used and mounted to front panel extension. This is parallel wired to large CW jack at rear side. TUNE BU

Improvements Made: • New small power supply • Built in Notch filter • Built in speech processor • Tune facility on the front • Built in preampl

SELECTABLE PREAMPLIFIER The sensitivity of the TR7 on the higher bands is sometimes too low. A preamplifier can improve the sensitivity of the recei

RV7 RENEWED I also renewed the remote RV7 VFO. It became the same styling and color of the renewed TR7 and power supply. Electrically the RV7

OTHER IMPROVEMENTS Fan The existing fan on the PA was replaced by a silent 12 volt version. I have reversed the flow direction of the fan for the P

CIRCUIT DIAGRAM PIN ATTENUATOR

Component Layout Component Side

PCB Lay Out Attenuator Scale 1:1

Part List Ref. Desinator(s) Qty Description R1 1 1k5 Widerstand,Resistor 1/8 watt, R2 1 39R Widerstand,Resistor 1/8 watt, R3 1 8

P8 1 22K Spindel-Trimmpotentiometer L1 1 68 µH, RFC, SMMC D1 1 BAR 28 D2 1 HP 3081 PIN Diode D3 1 HP 3081 PIN Diode D4 1 HP 308

NOTCH FILTER The simplest way to create a notch filter in the TR7 is to use an audio Notch filter. For the notch filter a dedicated PCB was design

TR7 RenovationSemi Automatisch Notch Filter Notch_Filter_14_09_2007DL/PA1HFO1 1

NOTCH FILTER PCB Component Layout Notch Filter (Scale 2:1) Solder Side Notch Filter PCB (Scale 2:1)

Parts List Notch Filter Ref. Desinator(s) Qty Description Grid R1 1 470 K Widerstand,Resistor 1/8 watt, R2 1 15K Widerstand,Resi

DSP NOISE REDUCTION Component Side Notch Filter PCB For the DSP noise reduction a modified NES 5 from BHI (UK) was used. www.bhinstrumentation.co.uk

DIGITAL AUTOMATIC FREQUENCY CONTROL THE PTO The PTO of the TR7 is continuously drifting. To overcome this problem a DAFC controller was built. The