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P. C. Electronics
Tel: (626) 447-4565 m-th 8am-5:30pm pst (UTC - 8)
2522 Paxson Lane Arcadia CA 91007-8537 USA
Tom (W6ORG) & Mary Ann (WB6YSS)
Email:

The Leaders in Amateur Television Equipment
Since 1965

SPECIALS and SURPLUS
Last Update February 6, 2010
From time to time we will announce and run special limited time promotions, list items that were built or purchased by us to be tested out on ATV, production samples, previous models, prototypes, over runs, surplus, etc.

Mary Ann gave me orders to stop being such a pack rat because it takes too long trying to find anything digging through piles of stuff - So please check back often.

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for Specials or go direct to: Power Modules, Semiconductors and Parts, Crystals

5 Watt 70cm 2 channel ATV Transmitter.........$499

This is the prototype unit that was photo graphed and built to test out the VM-70X packaging application note. It is built in the same die cast aluminim chassis that we used for our 1W TX70-1 transmitters. The unit is ready to go and we will wire the F1/F2 switch to which ever two 70cm frequencies you specify - 426.25, 427.25, 434.0 or 439.25 MHz. Click on the photo to see the photographs and details in the app note.
Operators Manual

MM downconverter 33cm ATV bandpass filter

I have a 2 cavity 33cm filter designed by DCI that was used in one of my portable repeaters. N jacks. It is currently tuned for 919.25 MHz, but I can retune it for your video carrier frequency. Price is $100.
The Spectrum International 426.25 MHz VSB filter also shown has been sold.

MM downconverter Micro Modules MM434-45 low noise crystal controlled downconverter

I found this downconverter which I used in my cross band ATV repeater back in the late 70's / early 80's. It was connected to the IF input of a 5" TV at the repeater site. Gain I just measured is 28 dB. Input is 434.0 MHz and output is 45.75 MHz IF. You could change the input frequency by getting another crystal. DC power is 13.8 Vdc at 60 mA. It is yours for $30.

TVCX-12 Crystal Controlled Downconverter and 23cm Preamps

This downconverter and preamp was taken out of service and they still work the same as the day they were put up.
This one is set up for powering a Downeast Microwave 23LNAWPQ antenna mounted preamp through the coax and is crystaled for 1253.25 input with TV channel 8 out. You could also receive 1265.25 MHz on channel 10 and 1277.25 MHz on channel 12 as an alternative. If you want another frequency, you would have to get a crystal from International Crystal Mfg and have it shipped to us to be plugged in and retuned. The downconverter antenna input is BNC, output is F.
The preamp is the first one made by DEMI - S/N 1 - and has marked on it .68 dB noise figure and 13.5 dB gain (should be a collectors item). Preamp has N jacks and powered through the coax from the downconverter. This downconverter, preamp and wall plug power supply all for $100.

23cm preamp Also available is a never used Downeast 23LNA20WP antenna mounted preamp, shown right, for $70.

Fp/Nj Adaptor...$3 price cut in half
F male plug to N female jack, 50 Ohm.
Use with cable ready TV to low loss 50 Ohm coax to 70cm antenna. 75 Ohm TV input mismatch is negligable.

FM ATV Pre-emphasis and De-emphasis Kits

Pre-emphasis in the FM ATV transmitter along with corresponding de-emphasis in the receiver can more than double the distance or add a P unit for the same distance (6 dB) by lowering the noise floor in the receiver. Pre-emphasis and De-emphasis is standard in the USA for 1200 MHz FM ATV systems - CCIR 405-1. However, most board level imported FM ATV transmitters and receivers do not have this feature.

You can easily add on by placing the transmitter PEK kit in the camera video line and receiver DEK kit in the video output line, and readjusting the video gain pots. See our FM ATV application note to see how easy it is. Kits include all parts, solder plated metal can and RCA jacks.

PEK Tx Pre-emphasis kit...$15
DEK RxDe-emphasis kit...$15
Buy them both at the same time and save $5... $25

GVM-1 Gunnplexer Video Modulator Board....$29

This is a board that has many other uses:
Video amp for satellite receivers
Video distribution amp
Sound subcarrier mixer
Pre-emphasis or de-emphasis amp
Download the NEW app note

Gunnplexers make a great little microwave (10.4 gHz) ATV link or way to demo ATV and how directional antennas work, bouncing off metal objects, multipath, etc., in a more interesting visual way at ham clubs or ham class rooms.

See the gunnplexer application note - A 10 gHz ATV system is easy to put together. Gunnplexers are available from SHF Microwave and Advanced Receiver Research. Choose those that have varicap tuning diodes in them - the GVM-1 modulator board connects to the varicap to DC bias and FM modulate the Gunn diode in the Gunnplexer.
Analog satellite TV receivers don't output enough video when used on the 900 and 1200 MHz ATV bands with 4 MHz deviation. This board can boost the level up to the 1 Vp-p standard with an adjustable gain up to 5.
Tapping into a video line without loading it down to drive a 2nd monitor, VCR, transmitter, etc., is another application of this board.
This board can also be used as a video and sound Mixer. Add sound with our FMA5-G board or FM pre-emphasis to video only ATV transmitters. The pre-emphasis can be removed for AM transmitters. The video amp has variable gain up to 5 which can better set up or equalize the video level in some transmitters - 75 Ohm input and output.
Modified for the ham bands wireless video transmitters and receivers can double the DX by adding pre-emphasis and de-emphasis to the video which lowers the noise bandwidth.

• • The boards are $29 if ordered individually, but for ham club or group projects, you can have them for 2-4 $25 ea, 5-9 $20 ea and 10 up $15 each. 25 left.

PA5 board..........$25

Ready to mount 70cm 20 Watt amplifier board with all parts including 6" RG-174 coax in and out pigtails soldered on - just add your M57716 power module, heatsink and chassis. We have a lot of these boards left over since we can no longer get the M57716 power modules in quantity - Used in our TC70-20 series of transcievers and PA5-20 amplifier module. However, you can still get the M57716 power module one at a time from RF Parts. You can drive this 20 Watt 70cm amp directly from our TXA5-70S ATV exciter board, Videolynx 434 or Z70A, or from the TXA5-RCb with an attenuator. Click on PA5 board above for the application notes.

TXTVb ATV Exciter/Modulator Board...$30

Great club or group project!
Transmit ATV over short distances.
Partially assembled board and selected parts kit - click on photo at right for full details.
Only..$30, 2 for $49, 5 for $99
Fully assembled and tested add $20 per board.
As seen on page 39 in the Winter 2006 ATVQ.

Make a low cost 70cm ATV RF Test Generator for tuning up receivers or antennas. Demonstrate ATV at a ham club, Scout Jamboree, Field Day, etc., with this unit - transmit in the building to a cable ready TV set. This board puts out about 10 mW and uses the same crystals as found in all our 420-450 MHz ATV transmitters - standard 70cm frequencies available from us. The board comes partially built (as shown in the photo) and with all 12 of the additional parts as a kit to complete the board. Assembly and tune up instructions using a DC Voltmeter are included - download and see the data sheet by clicking on the board photo above.

Or, by using a different crystal and additional parts kit, you can drive a 2 meter in / higher band out Transverter like those available from Downeast Microwave, SSB and others, you can add the AM ATV mode with this board. The boards are stuffed and soldered with the exception of the inductors, parallel capacitors and 3 2N5770 transistors which we will include as a kit (specify 2 M or 70cm) with each board for use on 70cm with 10 mW or 2 meters to drive a transverter with 50-100 mW. 70cm crystals are $25 and use the same ones as found in all our transmitters. We have a limited supply of crystals for ATV on 1265.0 (1268 MHz Transverter) or 1289.25 MHz (1296 MHz Transverter) at $5, or you supply the crystal (order from ICM catalog #473370 - 2 meter F/2 and HC-50 holder) for the frequency you want to end up with after mixed in your Transverter. We made a bunch of these in 1995 for use in our TVX series of export TV transmitters for channels 3 to 13. But not much later Amprex and Philips stopped making the companion 10 watt power modules and no similar power modules are available - that ended that product line. Size is 4x2.25" - will fit in a Hammond 1590C or D die cast aluminum box - and takes 8 to 14Vdc at 40 mA. Use the FMA5-G for sound.

Power Modules

Click on part numbers for data sheet.
200 mw max RF input, run on 13.8 Vdc
Bandwidths are actually wider than listed.

BGY-32

Parts

We have an excess of through hole parts that were purchased in large quantities before we started using surface mount parts:

2N5770 small signal TO-92 NPN RF Transistor used in our crystal controlled transmitters and downconverters for the oscillator and multiplier stages. Up to 50 mw at 400 MHz.
5 for $1, bag of 100 for $10 or box of 2000 for $150. 4500 in stock.

Motorola MRF901 low noise UHF preamp transistor.............$5 ea., 23 in stock.
Lower noise NEC NE64535 UHF preamp transistor.............$7 ea., 28 in stock.
NE25139 dual gate GaAsfet used in our surface mount downconverters....$10 ea, 13 in stock.
NE25337 dual gate GaAsfet used in our thru hole downconverters.......$8 ea, 44 in stock.
MRF966 Motorola dual gate GaAsfet used in early thru hole downconv....$3 ea, 25 in stock.
MM3734 Motorola TO-39 NPN used as the modulator in older TX......$7ea., 200 in stock.

Motorola MPN3404 TO-92 Silicon Pin Switching Diode. Used for T/R switching in our TC-1 Transceiver. $.30 ea. - 152 in stock.

2N/PN2907A small signal TO-92 PNP transistor. Used in our sync separator circuits and other products. Great general purpose PNP.
10 for $1, bag of 100 for $8, 1000 for $60. 2500 available.

IC's - DIP integrated circuits.
Click on IC's above or photo for the list of part numbers
and quantity available

2-8 pF ceramic trimmer cap - Sprague GKU6R000.
RF peaking cap (red top) used in our transmitters and downconverters.
10 for $10, 100 for $70. 1000 for $500. 3000 in stock.

Capacitors - disc ceramics, electolytics, etc.
Click on Capacitors above or photo for the list of values
and number available

Inductor / RF choke, .25 each or $20 per 100
1 uH (500 in stock), 4.7 uH (100 in stock), 10 uH (125 in stock) & 33 uH (400 in stock).

Resistors - leaded 1/4 watt carbon film, bags of 100 or 200 ....$1/100
Click on Resistors above for list of values
and number of bags available

Crystals $5 ea: we have a variety of HC-25 plug in crystals used in our downconverters
and transmitters before we switched over to synthesizers. Click on Crystals to see
the list of frequencies, quantities on hand and what they were used for.

Bias-T Parts Kit............$15

Power your Antenna mounted preamp on the 400, 900 or 1200 MHz band through the coax with this bias T. Great for powering Downeast 23LNAWPQ or 33LNAWPQ antenna mounted preamp from the ham shack. Insertion loss was measured at less than 1 dB. Kit contains LMB cad plated - solderable - metal box with lid, 2 BNC chassis jacks, feedthru cap, 100 Ohm 1/4W resistor,.22 uH inductor and data sheet.
Additonal 2x2x.88" cad plated metal can with lid, great for small projects...$2 each or 8 for $10.

Information about this server Artsci Inc.