Mixing reviews together of both products and companies/customer service results in product Rating numbers/Stars that do not reflect a valid Rating of the actual product.Ī review should provide useful relevant opinions of a product. The correct venue for these reviews is the eHam Community Forum "Company Reviews". The product reviews is not the correct place for reviews of customer service or companies/dealers/manufacturers. The reviews are not a Forum for two-way exchanges, product inquiries, general discussions, complaints, help requests, product repairs or modifications, or customer service issues. Products to be reviewed typically should be tangible ham radio related items such as radios, antennas, towers, test equipment, feedlines, etc.ĮHam's Product Reviews are intended to provide an opportunity to share an opinion, positive or negative, of a commercially available ham radio-related product or service.Ī valid product review is one where you have experience or knowledge of the product that you would like to share with others. If your new review has not been Approved after several days you can assume that it was found to not be within the product review T's&C's shown below during screening. Before adding a new product use the "Search" tool on reviews Home page to determine if that product already exists in a category.Ĥ. The delay can vary from minutes to a day or more.ģ. The delay is for new review screening and approval. There's a delay before newly submitted reviews are Approved and posted in eHam's reviews. eHam's Product Reviews are a database of ham radio related products and services personal opinions.Ģ. I know Ferrite isn't increasing in value! HI HIġ. There's about 35 Beads on a little piece of Coax inside that when stretched out to about 15 inches, they perform much better! If you don't take something apart and make it a better product, you're not a real HAM!
One problem I seen was these units when taken apart, are wrapped up over the top in stuffed into this short little PVC.Not good electronics design practice. I pulled the ends apart once since they didn't use enough PVC Glue! One TIP you might consider, Sand the PVC around the ends where water can enter, if you're gonna use these outside, Silicone the Water points for humidity and moisture entering! I put them Outside and inside, on Feedlines, on DIPOLES, on LOOPS, inside the house, Keeps the RF off of the FeedLine Jackets.Įven stabilizes and reduces the noise as well, quiets the the receiver Hash.
#Rf isolator ham radio install
You really need to install a couple of these. My choke sits at the base of the antenna so it isn't getting tossed around.
Mine does make some noise too and I am not sure why, but it doesn't seem to affect the performance. Someone mentioned some rattling inside the MFJ-915 enclosure. An impedance close to 50 Ohms showing little reactance is observed across frequency. I've swept the MFJ-915 from 1 to 30 MHz with the RigExpert and a 50 Ohm resistive load on the choke output. All is good on the other bands so I think the choking impedance is quite effective on all the bands the choke covers. No evidence of the common-mode problem, and now 10m is behaving as well. I then retuned the 15m wire element for the desired CW point and all is good. When I checked the impedance and SWR in the station they closely agreed with what I was observing at the base. Once added between the antenna and the RigExpert at the antenna base I found my 15m resonance moved up a 100 KHz, but the SWR was very nearly 1:1 at that frequency.
I decided to purchase the MFJ-915 isolator and see what results I would have. They helped, but the antenna resonant frequency and SWR varied between them. I tried a couple of homemade current chokes I had made from some -43 ferrite cores and coax. That of course is not the goal or desirable. That result was indication that there was a common-mode current flowing on the transmission line. Transmission line theory with a feedline having loss indicates that shouldn't happen. However, when I checked the impedance and SWR through the feedline in the station the impedance was off by quite a bit from 50 Ohms and it was also reactive. When it came to tuning 15m my RigExpert was indicating a feed-point impedance close to 50 Ohms and an SWR of about 1.1:1 at the antenna base. That is a very time consuming task and I could write volumes about that experience alone. I have a new Hy-gain, Hy-tower 80-10m vertical I have been working to tune on each band.
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