For best results support center at 30+ feet and ends over 15 feet. Angle of feed each side must be great than 45 degrees or 120 – 180 degrees total between each side preferred. Any length of 50 ohm feed line ok but longer feed lines over 50 feet may show reduced SWR on some bands due to losses in feed line and soil conductivity, nearby objects, etc. Due to local ground conditions, antenna height and feed line length, SWR may vary from samples shown and an antenna tuner may be required or some bands to bring SWR at end of feed line to acceptable levels. Overall length is 95+40 =135 feet. FREE Shipping on orders over $100 Insulators may be black, grey or white depending on stock at hand when order is placed. Wire is stranded, insulated and black color. 5KW antennas are made to order and take approximately 10 days after order to ship. SWR TECH NOTE:The SWR graphs shown are specific to the conditions listed including antenna height, configuration (flat top, inverted V, inverted L, etc.) and direction, feed line length and type, geographic location and soil condition, calibration and accuracy of SWR instruments used. Your SWR measurements will probably be different and manufacturer takes no responsibility or liability for these differences beyond the purchase price of the antenna. Chris Miller – Facebook 2/20/22 A tale of two very different antennas, and two very different companies... I started with the MyAntennas 75-10 strung across the top of a 15 foot hedge around my property, based on the company's claim on their website "Due to the High Impedance feed point, the antenna is less height-dependent. You can put it up at 10 or 50 feet in the air without much change in VSWR values."... Being new to the hobby and not getting the advertised SWR in this configuration, I reached out for help on the company's Facebook group... The owner berated me for not understanding how antennas work. I simply reminded him of the company's claim on their site. He would not reply to my emails, and kicked me out of the group... Fortunately there were a number of much more friendly and helpful people in that group that helped me to understand that height really does matter, despite the company's claim... So I used my drone to get the wire to the top of a tall palm tree on my property, and get very respectable performance out of the antenna... But being new, excited and curious, striving for knowledge and experience in the hobby, I wanted to see how the EFHW would compare to a similarly placed OCF... Palomar Engineers has multiple models that peaked my interest, so I reached out to the company to find out which model/configuration would work best. The owner of the company, Bob (AK6R) personally called me, asked questions about my location and my station, talked me through options, and explained to me the history and development of his "80-10 vertical radiator" model. This was the antenna he suggested based on the spacing and arrangement of palm trees at the QTH. Bob's willingness to share his knowledge and assistance was true to the spirit I have come to enjoy in this hobby... So over the weekend I contracted a tree service company to deploy the Palomar OCF just below the EFHW (You can see the ends of the two wires in the first photo, the EFHW terminating 5 or 6 feet above the OCF)... Performance is very similar where it counts as you can see from the SWR chart.... what's remarkable about the OCF is my noise floor drops 1 to 2 S units, which is huge for me, living in an urban environment where noise is obviously an issue... And of course the relatively flat SWR across the board, not just on points of resonance. I hope someone may find my experience between the two antenna types, or the two antenna companies, helpful. 73 KI6GEAOff Center Fed Dipole Antenna, 80-6 Meters (8 bands-including 15 meters), 500/1.5KW/5KW PEP rated - FREE shipping in USA
Excellent features:
*** Covers 80-40-20-17-15-12-10-6 meter ham bands
*** SWR < 2:1 on most bands, may require antenna tuner 80, 40 for full band use
*** 500 watts/1.5KW/5KW PEP (SSB-ICAS) options
*** Stainless Steel hardware for long life
*** Halyard Hoist for ease of installation
*** Insulated #14 wire for durability
*** High Strength insulators (may be black, white or gray)
*** 4:1 Balun and 1:1 Choke included in a single enclosure
Super convenient and quick – great for contest operation! Choose 500, 1500 or 5000 watt PEP (use 5KW model for digital modes over 1000 watts).
Unlike Buckmaster OCF antennas (at twice the price, and no WARC bands, 6 meter or 15 Meter operation, you can transmit and receive on 12,15 and 17 meters with our OCF - Better engineering and lower price - only from Palomar Engineers!
INSTALLATION
Note if you like the band coverage of this antenna but don't quite have 135 feet available, then consider the BULLET-8006 with very similar band coverage but only needs 95 feet of wire that is end fed.
Testimonial:
the ocf i purchased is the best working antenna i have ever had
wa6nrg john
NI5I: I was using a Buckmaster OCF, was given your 500 watt version second
hand, then bought your 1500 watt version from HRO last summer. I wanted
another. I love this antenna!
Iron powder cores are more stable than ferrites and do not saturate as easily so they are best for tuned circuits, filters, and high power inductors. They come in different “Mixes” for use at different frequencies. For best “Q” use the Mix specified for your frequency.To find the number of turns to give the desired inductance for your coil use the formula below:
Turns = 100 x 
Toroid Dimensions
To order specify core size and mix (e.g. T200A-2). Available in sizes that have µH per 100 turns shown in table.
All iron powder cores are special orders. Please allow one week for shipment after order received.
The iron powder cores shown in the above tables are primarily used for either high power feed line chokes for common mode current reduction or for 4:1 and 9;1 very high power transmission line transformers.
For high power feed line chokes, choose the inside diameter of the iron powder core closest to the transmission line outside diameter and use 6-20 cores at the junction with the antenna feed.
For 4:1 (50/200 or 75/300 ohm) transmission line transformers in the range of 1.8-30 Mhz, select the size appropriate for the power level as follows:
T200A x 2 = 1.5KW
T300A x 2 = 2.5KW
T400A x 2 = 5KW
Use Mix 2 for all the above transmission line transformers. Fully assembled and enclosed units are available for each of the power levels. Click HERE for information.
4:1 transmission line transformers using iron powder cores are typically used for ladder line to 50 ohm coax connections
For .1 – 2 Mhz wide band transformers use Mix 26 which has a higher permeability and requires less turns to achieve a given inductance. Mix 2 has almost constant permeability from 1-30 Mhz. Mix 26 has an initial permeability of 75 at .1 Mhz and gradually decreases to about 10 at 30 Mhz. For high power AM broadcast range (.5-1.7 Mhz) transformer, use Mix 26 to reduce the turn count.
Minimum order for iron powder cores is $50
Shipping on larger cores in quantity may be more than $10 – email/call for quote.