Home Theater RFI Kit

Bullet 50:200 (4:1) HF Unun, 1.8-61 MHz, 100/500/1500 Watts, End Fed OCF Antennas

SKU Bullet-4U-100
$69.95
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Bullet 50:200 (4:1) HF Unun, 1.8-61 MHz, 100/500/1500 Watts, End Fed OCF Antennas
Product Details
Brand: Palomar Enginees
UPC: Does not apply
MPN: Bullet-4U-100/500/1500
Type: NEW
Country/Region of Manufacture: USA

The “Bullet” End Fed OCF Antenna Matcher - 100/500/1500 Watts PEP/Digital

The key to end fed OCF antenna success is the matching network interface between the wire antenna and the feed line choke on the coax. Palomar Engineers employs a dual port ferrite matching system that offers wide bandwidth (1.8-61 MHz), and a 100 watt PEP power rating.

The antenna can be used as a sloper, “L” with a vertical section and a longer horizontal section, or as a horizontal or sloper antenna between two trees or supports. Great antenna for portable operations like NPOTA, SOTA, Field Day, etc., or for permanent installations like installing in an attic, under the eaves of a house, along a fence, etc. This is a short, effective and easy-to-hide antenna which gives a good account of itself on -80-6 (95' wire), 40-6 (55' wire) or 20-6 (25' wire) meter bands.

We sell the Bullet-4U-100 separately so you can add you own wire type and length (see table of suggested lengths below) or you can purchase a complete antenna system including wire and end insulator. Remember you also need a feed line choke like the easy adjustable snap on SOFLC.

If you need a higher power 4:1 unun for your OCF end fed antenna, check out the Bullet-4U-500 or Bullet-4U-1500.

Use a good quality 50 ohm cable such as RG-8X or similar as that size allows multiple (5-6 recommended) turns thru the feed line choke. The Bullet-4U-100 matching unit is rated for 100 watts PEP for SSB and 100 watts for CW/FT8. If the matching unit becomes warm to the touch after transmitting at high power, reduce the power output or the internal matching unit may become damaged.


NOTE: We rate our Bullet baluns (and ununs) VERY conservatively with a 50% duty cycle as used with digital (FT8) modes. Some manufacturers selling low cost baluns may use a 5% duty cycle for their PEP rating to make it appear you get a higher rated balun for a lower price, but you may in fact be getting be getting less. Their 1500 watts PEP really means 75 watts continuous or 150 watts at a 50% duty cycle compared to our 250 watts at 50% duty cycle. Our baluns typically cover a larger frequency range under 2:1 SWR which make your transceiver happy and probably will last longer with less electrical stress.

Remember we over engineer our products, to out perform our competition - just compare the weight of our products to theirs and you will know we put much more into our products so you don't have to worry about power saturation failure at a critical moment.

TECH NOTE: We also stock RFI kits to protect effected devices such as garage door openers, computers (laptops, desktops), dsl/cable routers, ethernet hubs and many more devices. If you run a high powered RF amplifier in your ham station also consider a linear amp RFI kit which will cut down RFI transmitted by your station. Remember there is always a “transmitter” and a “receiver” of RFI and the quest is to find and choke the “path” the RFI has selected – you need to add ferrites to both the transmitting side and the receiving side to eliminate RFI problems. The RFI-HTS kit only helps suppress RFI on the receiving side.

Typical RFI Problem/Solution:

Hello,
I am Larry, a ham operator and I am having interference issues with
my Direct TV system.
My station is a FT450D through an Ameritron ALS-600. From the amp
through a coax switch  to choose between an OCF dipole or an Hustler
5BTV vertical. Any power over 100 watts and my DTV goes off the air
and must completly reboot/format. Coax is RG-8. The DTV dish is
pointed away from the dipole and separated by about 25'. DTV was
totally useless! They suggested I not talk on the radio while she is
watching TV!  Please help me with a reasonable, cost effective
soultion. (The wife gets really pissed when I shutdown the tv!)

Thank you,

Larry 

 

Hi Larry,

Your RFI problem is quite common and is usually a sign of either a radiating coax feed line or reception of your radiated signal (source) by the Direct TV (the victim) through either the AC power lines acting as “antennas” for your ham signal or the coax braid of the satellite antenna acting as an antenna for your signal.

The solutions are straight forward:

1. To make sure your feed line is not radiating you need a feed line choke at each antenna feed point (also makes your antenna work better since it is not using the coax as part of the antenna).  You can use our simple Kit 110 with 5 snap on chokes on each antenna for this purpose.  Part # Kit 110 at $27.50 each – one for each antenna.  These chokes will keep your feed line from radiating and coupling into your ac power lines.  INFO HERE

2. The radiation from your antennas themselves may also be getting into the ac power lines and coax braid of the Direct TV antenna so you need to protect the victim receiver.  Depending upon the sophistication of your direct TV setup (e.g. home theater, dvd, tape player, sub woofer speakers, etc), the path of the RFI may be coming thru the AC power lines of any connected device to the video including the video monitor itself!  To help solve this problem we have a home theater RFI kit for up to 5 devices (you need a minimum of two – one for the Direct TV receiver(AC and coax input) and another for the video monitor AC power lines and HDMI or video input cable.  Our kit part # is RFI-HTS.  INFO HERE

These items should help reduce the RFI and let you operate on the air while your wife watches TV.

Bob Brehm, AK6R

Chief Engineer