ATTENTION: The price shown includes Greek VAT 24% and is applicable to all individuals in EU countries only. If you are from any other country including USA, Canada, Australia etc. please use the "make offer" button and divide the price by 1,24.We will first accept this offer to let you proceed with the check-out and payment. If you are a business registered in EU with a valid VAT number again, you can use the same button so to pay without VAT. We will send you a zero VAT tax invoice.

1.8 MHZ High-Pass Filter Built & Tested

 

TESTED ON TX WITH 10W FOR 1 MINUTE!

This eBay listing is for the Low-level Filter- For Receive only

This design is a 11th order Chebyshev high-pass filter with very low ripple.

It is offered in two variations, one low-power, for receive only applications and another capable of withstanding high power, i.e., capable to pass high power on all HF bands including 50 MHZ without the need to put it out of the line when transmitting up to 500 W or more. The damage level is 2100W.

A special enclosure, for each of the two variations, is also available and both PCBs are designed with those enclosures in mind.

There is no something high-tech on these filters, only, because many friends of mine were not satisfied from the performance of commercial low cost similar filters, asked me to develop a better one with more elements to give rapid attenuation of the MW BC band of 550 - 1600 KHZ, while to perform transparently on all of the rest of the HF spectrum with minimum loss. I have started the design thinking to sacrify the 1.8 - 2.0 MHZ amateur band (or, at least don't care about this band) because I didn't know how to get minimal loss on 160 m and deep attenuation on the area of 550 - 1600 KHZ at the same time. One solution was to use an elliptic design which provides rapid attenuation curve but only up to around -40 dB minimum attenuation of the rejected band so to be practical and easily reproducible at home,  and another solution was to use high-order and  carefully selected good components with the Chebyshev coefficients. With the chosen topology, an attenuation curve of around 10 dB per 100 KHZ has been achieved, -16 dBc on 1600 KHZ, (-20 for some prototypes),  --26 dBc on 1500 KHZ,  - 37 dBc on 1400... <-100 dBc under 800 KHZ and even more on 550 KHZ., while its maximum loss over the 1.8 to 54 MHZ range is on the middle of the 160m band with 0.4 dB, which is quite acceptable at lower power levels.

See more info at www.sv1afn.com under projects or directly to 

https://www.sv1afn.com/1m8highpassfilter.html  (copy and paste to your browser to work).

ORDERS For a complete Built & Tested Unit (USD 49.90 incl. 24% VAT)

If you have a valid EU VAT number please email us for issuing a VAT exception invoice. Or if you are from USA/Canada and all over the world except EU, you will not pay the 24% VAT, just press the "send offer" button and fill USD 40.24 instead of 49.90

The KIT includes a  high-quality ENIG FR4 PCB which is Built & tested, an alumimum enclosure (25 x 79.9 mm) that comes with all components factory soldered. 
RF capacitors are used for all the circuits.  Two SMA female connectors are placed for the input and output ports.
The shipping is with registered mail  (your signature is required upon delivery). 
I usually ship the next day and it takes about a week to 10 days for USA or Australia, less than a week for Europe.​