Tuesday, April 29, 2008

Manson SPS-9600 60 amp Power Supply

I have a Manson SPS-9600 switching mode power supply, this Goliath provides a Whopping 60 amp current which is need to power my TE Systems 0552G which draws a 55 amp load at top rating. There are just not many choices available with such current provision.

The Specs:

60 Ampere
1-15 Volt DC variable
13,8 Volt DC nominal operation
5 ampre front panel connection
LED Voltage & Current Readout
Size: 220 x 110 x 360 mm
Weight: 5.8 Kg

Main Output /Remote Sensing/ Remote Control/ terminals on the back.

Remote Sensing for remote point of regulation.

Remote control terminals for output voltage & current.

Light weight and small size.

Over-temperature /Short Circuit Protection.

Constant Current Limiting Protection with LED indicator showing overload.

Variable speed thermally controlled fan.

High RFI stability.

Power factor correction >0.97.

Active Power Factor Correction.

Load Regulation: 0.1%+5 mV

Line Regulation: 0.05%+3 mV

Ripple & Noise (peak-peak): 30mVp-p

Input Voltage: 230V AC / 50Hz

Efficiency (output 15V 60A): > 85%

Meter Type: LED Meter - V meter Range 3 digit display, A meter Range 3 digit display

Meter Accuracy: +/- 1% +1 count

Protection Devices: Overload (Constant Current Limiting), Short Circuit, Over Temperature, OVP.

Cooling System: Variable Speed Thermally Control Fan

Special feature: Remote Sensing, Remote Control

Approvals: Designed and manufactured to comply with CE

Monday, April 28, 2008

Yaesu FT-221 144MHz Transceiver.

Installed at the QTH is an old but reliable Yaesu FT-221 fitted with a Mutek Front End Board for monitoring of SSB on the lower portion of the 144MHz band for possible long distance contacts with BV. This was quite a common occurrence at my last QTH during the last cycle and a good number of BV contact were made.

About the Mutek Front End Board:

RPCB 144ub Replacement board for the Yaesu FT221 and FT225 Transceivers -

Mutek Limited produces a series of high performance RF/IF replacement boards for the FT736, IC251, IC271, TS700S, FT221, and FT225 that will turn any of these radio's into competition grade high performance receive systems. These boards are a redesign and replacement of the radios RF preamplifier, lossy PIN diode antenna changeover switches, bandpass filters, mixer, and IF amplifier section including in most cases the crystal filter. Low loss antenna relays, low noise preamplifiers, three pole filtering plus high dynamic range shottky Double balanced mixers (DBM's) and high quality crystal filters are featured in muTek's replacement boards. The addition of a muTek board will yield a radio with an excellent noise figure and a high dynamic range ----- performance that you could only dream of in the past.

The RPCB 144ub is the replacement board for the Yaesu FT221 and the FT 225 transceivers. It is supplied with complete installation instructions as well as interconnecting cables. The board replaces the original board in the transceiver and is the simplest of the front end kits to install. This board features a low noise front end, Tchebyshev bandpass filters, diode ring Double Balanced Mixer (DBM), IF amplifier plus an 6 pole 15KHz crystal filter. No alignment is necessary after installation of the board.

Technical description of Yaesu FT-221:

Frequency Range 144.0 MHz ~ 148.0 MHz

Emission: AM FM SSB (LSB and USB) and CW

Power Output:
SSB 12 Watts PEP
FM, CW 14 Watts
AM 2.5 Watts

Principle: Superhet with RF-stage; IF-Freq. 10700 kHzSuperhet with a preamplification stage. Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil)Permanent magnet type moving coil speaker (principle by Rice-Kellog, without field excitation coil).

General: Dimensions (WHD) 280 x 125 x 295 mm / 11 x 4.9 x 11.6 inch

In FM-mode double-conversion, second IF 455 KHz. Later "R"-version have modified frequency-offset-control for FM-repeater operation and few minor changes on back-panel. In Europe also sold under Sommerkamp label.

The frequency is set by a 500KHz VFO being mixed with the product of a number of crystals and is displayed using a rotary display dial.

The top of the case is removed by opening 4 quick release fasteners, revealing a number of user adjustable trimmers and pots. The modular design of the FT-221, where removable circuit boards allowed radio hams to modify their FT-221 either by replacing specific components or even replacing the whole board [Mutek]. One such replacement is the mutek replacement front end board which improved the front-end sensitivity. The open format of the internal construction also allowed the transmit and receive cables to be brought outside the case to use a low-noise coaxial relay.

Below is a photo of the 5 element Diamond yagi antenna installed and point roughly 5o deg. The black coating is high temperature black paint sprayed on to prevent aluminium corrosion:

Below is the Mutek direct plug in replacement Front End Board for the FT-221 transceiver:

Sunday, April 27, 2008

Philips Rotor Control Unit & Russian 50Ohm RF Load

Photo below shows the Philips programmable rotor control unit in my shack which control the 50MHz HB9CV Yagi antenna:

I have a Russian 50Ohm RF load which was dismantled for ex Russian Communications equipment, the rating is 150 watts. I will need to fit it into a case with suitable RF socket for use as a 50Ohm RF load. See below the dismantled russian RF load:

Saturday, April 26, 2008

50MHz 2 Element HB9CV Phased Beam Antenna

The 2 Element Diamond HB9CV Yagi-uda 50MHz antenna had been assembled for two weeks but had be sitting on the roof awaiting to be installed because the waether had been bad. Finally with the assistance of Charlie, VR2XMT we had a chance to install it on the afternoon of the 26th April, 2008 (Saturday) as there was a spell of good weather.

Below is a photograph of the erected antenna shortly after installation on my roof.

After installation a comparrison was made with a 50MHz vertical and it was immediately apparent that the noise was much less on the horizontally polarized Yagi-uda making it more suitable for long range DXing, a Philips light weight programmable azimuth rotator is used for steering beam in directions require. The control box is digital with it's own infra red remote control and can store uop to 12 memories for beam headings.

Below in a simple beam heading azimuth chart that was run on the computer. The center is Hong Kong and this is a Great Circle beaming heading map. For example Europe is 330 degrees.

Below are the specifications for the HB9CV antenna which is also RoHS compliant:
A502HBRFrequency:50 to 53MHz(Center frequency without adjustment is set to 51MHz)
Power rating:400W(SSB)
VSWR: Less than 1.5:1(50 to 52MHz without adjustment)\
FB ratio : More than 15dBHalf power band width: Less than 70degrees
Wind surface area:0.14m2 Rated wind velocity:40m/sec.
Turning radius: approx.1600mm
Connector:M(M-J) Mast diameter accepted:25mm
Dimensions:800mm x 3000mm x 85mm