What is a Roofing Filter?

On a recent club net, one of the stations checking in, asked about roofing filters. The roofing filter in a radio is the filter through which the first IF must pass. According to Elecraft, the term "roofing filter" has most often been used in relation to triple- or quadruple-conversion receivers. Such receivers have an IF above the highest RF band covered; it's typically something in the range of 30 to 70 MHz or higher. But "roofing" as a term should be interpreted as "protective," not "high in frequency." A roofing filter protects later stages, including amplifiers, mixers, narrower filters, and DSP subsystems, just as the roof on your house keeps rain out of all of the rooms.


Pasted Graphic


Roofing Filters in Context

A YouTube video discussing adding a roofing filter to enhance CW operation: https://youtu.be/CIRJqBGRCUI?si=1l8_pj6VfnoSKcSi

Demo of roofing filter on 20 meters: https://youtu.be/mKnoxmjNstI?si=ef7yik0zRg_touab

A YouTube video about installing a roofing filter in a Yaesu radio: https://youtu.be/5Af9Je-JrNw?si=pnyGyU0wKToQGcWH

Here's another video about the difference between roofing filter and DSP filter: https://youtu.be/_FRkpfGh7Ik?si=g6LTjqKtFgmMhSRR

Zoom Link for Tim Joynes Memorial Service

Zoom Link for Tim Joynes KB3IUM/SK memorial service on Sat. 6/1, 2-5PM:
https://bit.ly/KB3IUM

Memorial Service for KB3IUM/SK

A memorial service for Tim Joynes, KB3IUM/SK will be held on
Saturday June 1st from 2pm to 5pm
at:

Hyatt Place Wilmington Riverfront,
760 Justison St., Wilmington DE 19801.

A Zoom link is forthcoming. Please pass this news along to all Hams you know. It would be great to have a big showing to honor Tim.





KB3IUM is a Silent Key

Our friend, Tim Joynes KB3IUM became a silent key Saturday, May 11, 1330 hours. A friendly voice on the Delaware City repeater and regional DMR nets, he will be missed. Information regarding arrangements will be posted here as soon as we learn of them.

30403_1459551767158_1344570_n



MFJ: the End of an Era? Are They REALLY Going Away?

mfjbrands


MFJ Enterprises, founded in 1972 by Martin F. Jue K5FLU, manufactures a wide range of products for the amateur radio market. They specialize in station accessories, such as antenna tuners and antenna switching equipment. According to Wikipedia, MFJ manufactures more amateur radio products than any other company worldwide.

The company announced last week that it will cease on-site production in Starkville, Mississippi, on May 17, 2024. The same applies to its sister companies, Ameritron, Hygain, Cushcraft, Mirage, and Vectronics.

Screenshot 2024-04-29 at 5.37.15 PM


In a letter dated April 25 and shared with customers and dealers, Mr. Jue noted that he recently turned 80 years old and wrote, “I had never really considered retirement, but life is so short, and my time with my family is so precious.” He cited the COVID-19 pandemic as a cause of a downturn in business from which the company never recovered.

It would appear that all the Internet hype about MFJ going out of business is just that—hype. In the absence of any other market data or business intelligence, the only information we have is in the letter itself. We know that manufacturing operations are shutting down and that Martin F. Jue is likely not to keep office hours going forward, but the letter does not specifically say MFJ is going out of business.

“We are going to continue to sell MFJ products past May 17, 2024. We have a lot of stock on hand. We will continue to offer repair service work for out-of-warranty and in-warranty units for the foreseeable future.”


The letter states that MFJ products will still be sold, and stocks are currently high. It also points out that MFJ will continue to offer service and warranty repairs. So, the MFJ name is not going to disappear any time soon. What goes forward now is open to conjure. It is possible that MJ will find offshore manufacturing options. OR, it may sell the brand to another company that will find those manufacturing options.

At this juncture, the horizon is wide open. There could be potential collaborations with dealers like GigaParts or Ham Radio Outlet. During this transition, we might witness a streamlining of the product range, with slower-moving items being phased out. Suppose a retail partner like GigaParts or another company were to take over the MFJ portfolio and make it their house brand. In that case, they would likely discontinue the slower-moving items. Some of the MFJ brands, such as Cushcraft and Hygain, could potentially be acquired by other antenna companies like Diamond or Comet. The only certainty we can draw at this point is that the MFJ brand will continue to have a presence in the marketplace, albeit to a certain extent, and that Mr. Jue is set to enjoy a well-deserved retirement.


mfj_thumbnail
Click to read the letter

K3JRZ POTA Activation and ISO-3166 changes to U.S. POTA sites

Jeff K3JRZ stopped at US-10688 Tubmill Pond State Fishing Lake @delawarednrec, in Milford, Delaware, on Friday March 29, 2024, for his first Parks On The Air @ParksOnTheAir (POTA) activation after the ISO-3166 standard change to U.S. POTA entities. Previously, all U.S. parks were defined by the prefix KILO "K."

Friday Nite 6m Net

Join us every Friday night at 8:00 PM local time when we ham it up for the Friday Nite 6 meter Net on 50.160 MHz, mode: USB!

AdobeStock_756914588-squashed

April 18, 2024 - World Amateur Radio Day 2024

ARRL_WARD_Logo_original_F_version_525_wide
World Amateur Radio Day (WARD) is April 18 and is celebrated worldwide by radio amateurs and their national associations, which are organized as member-societies of the International Amateur Radio Union (IARU). Read More…
© 2024 Delaware Valley Friends Ham Radio Club. Contact Us