eHam.net - Amateur Radio (Ham Radio) Community

Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net


Reviews Categories | QRP Radios (5 watts or less) | MFJ 94-Series Help


Reviews Summary for MFJ 94-Series
MFJ 94-Series Reviews: 72 Average rating: 4.4/5 MSRP: $239.95
Description: SSB Travel Radio (CW optional)
Product is in production.
More info: http://www.mfjenterprises.com/index.htm
Email Subscription
You are not subscribed to this review.

Subscribe!
My Subscriptions
Subscriptions Help

You can write your own review of the MFJ 94-Series.

<— Page 2 of 8 —>

WB4JHS Rating: 5/5 Apr 12, 2013 15:02 Send this review to a friend
Works great mobile  Time owned: 0 to 3 months
I was a bit skeptical of th 9420 but I need an innexpensive mobile for 20M that won't break the bank if it gets stolen. This looks like a CB to most who would look though the window. I use it with a hamstick and great results. I have worked Dx from SA to EU and the Caribbean to greater USA. The radio will drift for the first 15-20 minutes and the ignition noise of my 2012 Chevy Equinox is a problem but not a show stopper. If you have suggestions on how to kill the whine of the alternator please advise. I hope to take to Panama C.A. this June to DX from the balcony of the resort over the pacific coast. Folks on 20M give me S9 to 10 over often. The stock mic works better than the Workman replacement that I read about in this thread. Email if you want to discuss the 9420. John jmahagan@bellsouth.net
 
KF7RCM Rating: 3/5 Dec 12, 2012 20:55 Send this review to a friend
I purchased a 9420 with the mic.  Time owned: 0 to 3 months
The reason I gave it a 3 is due to the fact that the mic that came with it in a word "sux". I recomend that if one were to get one, get it with out the mic. No matter what I did to make it function, it only distorted the audio output. I got a Super Star DM-507-5r 5 pin din mic off ebay for about $10 and it works great. That said, coupled to 2 MFJ's 20 meter hamsticks and the bracket that allows one to make a horizontal dipole out of them, mounted a little more than 30' up, I easily made QSOs on the eastern seaboard. Not bad since I am north of Phoenix, AZ and desert soil is'nt very good for this sort of thing. Set it up on my F-150 in a mobile configuration and made it to the southern states. I dont have the CW mod and not going to get it. I would like to have a digital freq counter mod available though. Not a bad little radio. Will update this review as needed.

The connection is a 5 pin din for a radioshack/realistic radio.
 
VE3GZB Rating: 1/5 Dec 9, 2012 09:56 Send this review to a friend
Waste of money  Time owned: more than 12 months
I've owned my MFJ9420 over a year now and even on a dipole 35 feet up in the air, where my TS2000 or TS820 on 10 watts can QSO over to France and Italy on the same antenna, in all of this time I've only ever had one successful QSO with the 9420 and it was only on the North American contintent.

It does receive ok, and according to the SWR meter in my tuner it is putting something out and the SWR is unity.

I would not recommend this radio at all, unless you have cash you can afford to waste.

73s VE3GZB
 
VE3GZB Rating: 2/5 Dec 7, 2012 05:57 Send this review to a friend
Ok but....  Time owned: more than 12 months
I finally managed to QSO with my MFJ9420. I did run into a problem however.

Since I use it with lightweight rechargable Lithium batteries, their output voltage will fall as they discharge.

What I've found is that a given mic gain setting that works at a lower DC input voltage will cause trouble if a freshly charged battery pack is used with the radio, and it is a pain to have to fiddle with it to get it to behave.

My solution was to install a standard TO-220 Non-plastic case 7812 voltage regulator within the case of the '9420.

It's not hard. Here's how you do it.

First prepare the 7812 with suitable bypass capacitors on the input and output side. For the input side I used a 220uF in parallel with a 0.1uF cap.

On the output side I used 10uF in parallel with a 0.1uF cap.

Now on the circuit board? From the DC connector look for a zig-zag skinny trace. This is a fusible link. Cut it with a knife somewhere in the middle. That breaks the unregulated DC input.

Loosen and remove one screw and nut from the RF output connector and use that as a mounting point for your 7812. By grounding the tab of the 7812 to this point, you complete your grounding.

At this point, tie your regulator input to the DC input connector V+ pin and your regulator output to the other side of the fusible link which you previously cut.

Now your radio's mic gain and performance will be consistent despite variations in your rechargeable battery voltage.

73s VE3GZB
 
VE3GZB Rating: 1/5 Oct 30, 2012 12:52 Send this review to a friend
Not much luck  Time owned: more than 12 months
I bought a 9420 last year in hopes of taking it into the forest and working some clandestine DX QRP.

But first I connected it up to my 20/17m homebase, with a helical dipole, balanced feedline and balanced tuner which I've successfully worked multiple countries.

I could hear plenty of activity on 20m. I know I was tuned up for minimum SWR. I know the transceiver was drawing current as I spoke into the mic.

But even at maximum output I was not heard.

I disconnected the radio and put my TS-2000 back, fired it up on 5 watts and managed QSOs.

So while the MFJ-9420 seems like a novel and cute idea, it would help a lot if it would actually work. To this day it just sits under my bench, gathering dust. It seems to be well qualified to do just that.

73s,
VE3GZB
 
VE2BXJ Rating: 3/5 Oct 9, 2012 16:11 Send this review to a friend
SSB fine, CW board awful  Time owned: more than 12 months
It's fine for SSB and I have made it work for digital modes using a mod to make SSB work on the lower portion of the band (needs the CW add-on board).

But for CW, don't even bother. The side-tone alone is enough to make you go nuts. It's more like a squeal than a tone. Don't buy this radio if you're planning on using it for CW. I sold my MFJ-9420 and used the money to get a FB1B.
 
EA1HFI Rating: 5/5 Sep 24, 2012 23:39 Send this review to a friend
Un QRP Excelente!!  Time owned: more than 12 months
El 9420 se describe como un "equipo portátil" pero es sobre todo un transceptor de SSB, aunque se le puede añadir CW con un modulo plug and play. Con esta pequeña belleza y sus 10 vatios PEP es fácil de lograr muchos contactos agradables, ya sea desde base, móvil o lugar de vacaciones. Funciona con un voltaje nominal de 13.8, y un consumo de 2 amperios en transmisión, por lo que una pequeña fuente de alimentación o unas baterías de NiCad pueden ser utilizadas.
El micrófono es de la impedancia habitual de 600 ohmios y del tipo dinámico, el único requisito extra para estar en el aire que es algún tipo de antena de 20 metros.
He utilizado este equipo desde la estación de casa con mi dipolo y he tenido varios contactos DX, entre ellos EEUU, Canada, Japón o Kasajistan, también he tenido muchos contactos por Europa.
Al ser una plataforma compacta es ideal para el uso portable ya que con solo una pequeña batería o fuente de alimentación, un balun 9:1 y 17 metros de cable puedo salir al aire desde un prado, montaña o el balcón de un hotel .Con esta configuración he realizado muchos QSOs entre ellos Escandinavia, Alemania, Irlanda, etc.
Con una antena telescópica de 2 metros de largo reciclada de un Walky y un balun de 10:1 LMZ-50, también he realizado varios contactos por Europa!
La calidad de audio en transmisión es excelente, debido sin duda a el procesador incorporado, he tenido excelentes informes de audio no solicitados.
Hay pocos controles en el panel frontal, el VFO, volumen , conector de micrófono, un medidor analógico, un par de LEDs, un interruptor de encendido y otro botón para "sintonizar" que lo que hace es emitir una portadora de baja potencia para poder ajustar con el acoplador externo las estacionarias. El receptor de audio y la selectividad es muy aceptable.
En la parte posterior, sólo se encuentra la entrada de CC y el conector de antena, sin embargo, hay agujeros para la placa opcional de CW (que yo tengo instalada) también hay un pequeño orificio por donde se accede al potenciometro interno de ganancia de micrófono… Y ya está! No hay DSP ni memorias, ni frecuencimetro digital, ni nada mas! , usted sólo tiene que enchufar el equipo y operar, es tan simple y sencillo como eso y funciona muy bien. Hay un poco de deriva al encender el equipo en frío, pero después de un par de minutos la frecuencia es de roca sólida.
El PA es un robusto MRF477, pero hay que tener cuidado, por supuesto, y darle una carga de 50 ohmios.

Modificaciones
Ninguna modificación es realmente necesaria, pero yo le he realizado (por ahora) un par, he puesto una salida de auriculares en la parte frontal del equipo y es muy útil para lugares ruidosos o escuchar mas "fino". La otra modificación fue agregarle un portafusiles exterior en la parte trasera.Esta modificación fue un poco forzada ya que en un descuido se invirtieron los cables de alimentación y le dije adiós al fusible interno que viene en la placa PCB (realmente no es muy buen sistema). Afortunadamente hay un diodo montado en paralelo, seguro pensaron en mi!, así que no hubo ningún daño en el equipo! ¿Crees que nunca lo harás verdad?, yo pensaba lo mismo !…
Estoy dispuesto a recomendar el MFJ 9420 como un eficiente y pequeño equipo SSB para la banda de 20 Mts., aunque el precio es un poco alto en Europa (alrededor de 300 euros). El principal proveedor en Europa se encuentra en el Reino Unido y se llama Waters and Stanton (tel: 01 702 205 843), con la que no tengo ninguna relación comercial, ni tampoco con MFJ.

Especificaciones técnicas:
•Cobertura de 14,150 a 14,350 MHz transmisor-receptor superheterodino de simple conversión
•OFV: 4,150 a 4,350 MHz
•SI: 10 MHz (acceso por escalera de filtro utilizado)
•SI selectividad 6 dB a 2,5 KHz
•AGC - derivados de audio
•Audio: más de 1 vatio en el altavoz incorporado de 8 ohmios
•TX picos de 2 amperios (13.8 voltios)
•Consumo en RX, 50 a 100 mA
•Salida de 10 vatios PEP
•CA 03:01 tolerancia
•TX de audio: la compresión de RF del procesador, 600 ohmios micrófono
•Medidor analógico, unidades S en modo receptor, y potencia / ALC en transmisión
•CW disponible en forma opcional en formato plug and play
 
ON6KE Rating: 5/5 Sep 8, 2012 13:59 Send this review to a friend
Can't believe this.  Time owned: 0 to 3 months
I bought myself a 9420 (the new version with fine tuning) today in The Netherlands, came home in Belgium and started playing in the late afternoon right away with this little radio.
Today is September 8th so it's the WAE SSB contest, OK they need the points.

I worked Asiatic Russia several times in the afternoon, North- and South America as of 20:00Z and Africa with an EA8 all of it with 10 Watts PEP, 5 continents.
Tomorrow I'll get up and try working Oceania for continent #6, wouldn't that be something!!
Before I forget, my antenna is a low 20m Windom,

This little gem is full of life, it's pretty stable if you give it a few minutes after switch on and it's PUNCHY, I've heard it on my TS590S with a dummy load as antenna.

It's going to be fun when I take the rig with me on vacation to Malta mid-September!!



 
N3APA Rating: 5/5 Jul 15, 2012 16:17 Send this review to a friend
works good  Time owned: 0 to 3 months
Ordered a mfj-9420 & 971 tuner directly from MFJ in April. After adjusting the mike it worked perfectly right out of the box without the alignment problems noted in earlier reviews. Using a Par 20m endfed antenna in a vertical position from a tree limb it receives well. I called cq when I first turned it on and made qso's with Colorado, NM & SoCal from my NorCal QTH. Worked the IARU contest this weekend and made 11 QSO's in 2hrs: Tx,Mt,SC,Mn,Va, 2 in MD & La. Also had 3 dx Qso's: Chile, Argentina & Japan. All from my Northern California QTH. Had several that I couldn't complete but at least they heard enough to answer my call initially.
I realize that the antenna is at least half of the success but all in all I'm pleased with the rig. It's a lot of fun to operate.
When I placed my order I emphasized that I wanted the rig to be aligned and operate as expected. Perhaps my comments helped ensure that the quality control had been done. In a follow up call to MFJ tech support on another unrelated item I mentioned my pleasure with the 9420 and they related that they had been working on the production line to improve the quality issues that plagued some of the earlier units.
Great unit which I would again.
 
GM3HNN Rating: 5/5 Apr 26, 2012 06:41 Send this review to a friend
Long Live QRP!  Time owned: more than 12 months
At first glance, it looks like a 1970's old CB!!, but on operation, superb!! I only work QRP, and have worked the world with these things..I use the CW version + the 9420, always good reports, and yes, the build could be a bit tighter, but for the money and the fun, its just superb! Great fun outdoors, through a wire antenna over a tree, and away you go!, I also use the 971 ATU, just to get it perfect, recently worked far side of Russia from the beach at Brighton, showing around 5watts! so cant be bad, every ham should have one of these, well done MFJ
 
<— Page 2 of 8 —>


If you have any questions, problems, or suggestions about Reviews, please email your Reviews Manager.