you guys must be blowing some real watts out, here in my shack with an Omega with the rfx75 or the 257HP on a 20 amp Astron with the voltage set at 14.0 it never goes below 13.6 on my LED Meter, both radios's doing like 40 to 50 watts
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MAGNUM 257 HP Review
- Thread starter Robb
- Start date
With SSB: 65W PEP on an Astron RS-20M I get peak amp draw of 15 and see no voltage drop. Typical draw is 10-12 amps.
I use a heatsink fan to protect from overheating.
a
When they work correct they are Great radios, I think this last batch of them are just a problem that's why I sold my new one when I got it back and it worked. Bought a used Omega Force and am enjoying the heck out of it
general observations and improvements
Observations
1. Can only tune across the band in 10kHz steps. 1kHz step works only within a 10kHz range.
2. The ERF-7530 power transistor is very senstive to frequency. At 28MHz max SSB output is 65W PEP; at 29 MHz even less; at 27 MHs 75W+
3. Receiver very sensitive to ignition and electrical noise
4. If power to radio is off for more than a couple days, all custom settings lost... radio goes back to factory defaults
5. Excellent AM modulation, fair SSB modulation (separating mic gain from compression would be nice); FM modulation very week
6. Needs heat sink fan
Plus:
1. Sensitive Receiver
2. Excellent power output/price, i.e, good value
3. Like the blue display
4. Easy to set frequency coverage to 27Mhz
5. Quality manufacture
Observations
1. Can only tune across the band in 10kHz steps. 1kHz step works only within a 10kHz range.
2. The ERF-7530 power transistor is very senstive to frequency. At 28MHz max SSB output is 65W PEP; at 29 MHz even less; at 27 MHs 75W+
3. Receiver very sensitive to ignition and electrical noise
4. If power to radio is off for more than a couple days, all custom settings lost... radio goes back to factory defaults
5. Excellent AM modulation, fair SSB modulation (separating mic gain from compression would be nice); FM modulation very week
6. Needs heat sink fan
Plus:
1. Sensitive Receiver
2. Excellent power output/price, i.e, good value
3. Like the blue display
4. Easy to set frequency coverage to 27Mhz
5. Quality manufacture
Hello
My name is Adriano and I live in Brazil in Sao Paulo
In the month of December 2011 bought three units Magnum 257hp.
All three radios had the same problem.
I'm not sure that I speak, but the little I know think this problem comes from rfx75 because ese problem appeared after putting in bandwidth and increase power to maximum.
I paid $ 400 each, but they all showed me this defect
Please help me because if I send the radio to Sam Lewis, I'll never speed again by the bureaucracy of my country's Customs House
Magnum 257 HP operating on SSB (AM and FM works fine). If i Transmit
it works fine, but when i release the Mic button (after TX) in the
Were the bottom side Should Be RX level, it somth Appear like a signal
level 3 to 5 (constant and continous), but i can not get any reception
at all. Only if i turn the TX power level to transmit MAXand i, then
it goes back to reception, but not Every Time. Somtime i need after TX
to push the mic button 2-3 times to make it recive somthing, but this
wors only if the power level is 60-70% over an i repeat, only on
SSB.Can i get some help with this issue?
tks and 73 "
My name is Adriano and I live in Brazil in Sao Paulo
In the month of December 2011 bought three units Magnum 257hp.
All three radios had the same problem.
I'm not sure that I speak, but the little I know think this problem comes from rfx75 because ese problem appeared after putting in bandwidth and increase power to maximum.
I paid $ 400 each, but they all showed me this defect
Please help me because if I send the radio to Sam Lewis, I'll never speed again by the bureaucracy of my country's Customs House
Magnum 257 HP operating on SSB (AM and FM works fine). If i Transmit
it works fine, but when i release the Mic button (after TX) in the
Were the bottom side Should Be RX level, it somth Appear like a signal
level 3 to 5 (constant and continous), but i can not get any reception
at all. Only if i turn the TX power level to transmit MAXand i, then
it goes back to reception, but not Every Time. Somtime i need after TX
to push the mic button 2-3 times to make it recive somthing, but this
wors only if the power level is 60-70% over an i repeat, only on
SSB.Can i get some help with this issue?
tks and 73 "
This was the response from Sam Lewis
I did not understand much
Please help me solve the problem of my three radios
thank you
responder a saml@rflimited.com
para "Adriano Ignácio (Julia e Arthur Ignácio)" <adriano1972.35@gmail.com>
cc chris@superiorcb.com
data 27 de fevereiro de 2012 16:36
assunto RE: Help my 257hp Sam. Please
Importante principalmente por causa da sua interação com as mensagens nesta conversa.
ocultar detalhes 27 fev
Good afternoon
From your description it sounds like the radio is breaking into parasitic
oscillation on SSB. To determine if the radio is going into this
self-oscillation, do you have an RF wattmeter that you can install inline?
If you do then please put the meter inline and when you release the PTT on
SSB, if you see any reading on the wattmeter then you know there is an
oscillation. You can further confirm this by turning full CCW the mic gain
control, if you see any reading on the wattmeter than this is the problem.
If you see the oscillation, open the inspection plate on the amplifier
section (RFX 75). Check to see if there is a red mylar 1000pf cap that is
connected to the center lead of the driver transistor ERFf 2030 and the
final transistor ERF 7530, advise if this cap is installed.
Thank you
Sam Lewis
I did not understand much
Please help me solve the problem of my three radios
thank you
responder a saml@rflimited.com
para "Adriano Ignácio (Julia e Arthur Ignácio)" <adriano1972.35@gmail.com>
cc chris@superiorcb.com
data 27 de fevereiro de 2012 16:36
assunto RE: Help my 257hp Sam. Please
Importante principalmente por causa da sua interação com as mensagens nesta conversa.
ocultar detalhes 27 fev
Good afternoon
From your description it sounds like the radio is breaking into parasitic
oscillation on SSB. To determine if the radio is going into this
self-oscillation, do you have an RF wattmeter that you can install inline?
If you do then please put the meter inline and when you release the PTT on
SSB, if you see any reading on the wattmeter then you know there is an
oscillation. You can further confirm this by turning full CCW the mic gain
control, if you see any reading on the wattmeter than this is the problem.
If you see the oscillation, open the inspection plate on the amplifier
section (RFX 75). Check to see if there is a red mylar 1000pf cap that is
connected to the center lead of the driver transistor ERFf 2030 and the
final transistor ERF 7530, advise if this cap is installed.
Thank you
Sam Lewis
Adriano my 257HP did the exact same thing, got it in Decmeber too, I sent it back 2 times and it still worked the same, finally they sent me a new radio, sorry I can't tell you how to fix it because they didn't fix mine they just replaced it which is what Sam Lewis will probably do in time. Good luck my radio friend
Hello, Tucker442
I live far away, please help me solve this problem with Sam Lewis.
I bought the radios in Gijoes email and they do not respond, the site went off the air Gijoes
I can not stay with this prejudice, for I am poor and bought radios to resell here
Talk to Sam for me
My English and bad
thank you very much
I live far away, please help me solve this problem with Sam Lewis.
I bought the radios in Gijoes email and they do not respond, the site went off the air Gijoes
I can not stay with this prejudice, for I am poor and bought radios to resell here
Talk to Sam for me
My English and bad
thank you very much
Buenas tardes,
¿Está teniendo problemas para entender el e-mail sólo por el Inglés, o porque no entienden la parte electrónica de la misma?
Aquí está el correo electrónico traducido al español si eso te ayuda.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Buenas tardes
Desde su descripción suena como la radio se está rompiendo en parásitos
oscilación en SSB. Para determinar si la radio va en esta
auto-oscilación, ¿tiene usted un vatímetro de RF que se puede instalar en línea?
Si usted, por favor, poner la línea metro y al soltar el PTT
SSB, si usted ve cualquier lectura sobre el vatímetro a continuación, usted sabe que hay una
oscilación. Además, usted puede confirmar esta girando hacia la izquierda toda la ganancia del micro
de control, si usted ve cualquier lectura sobre el vatímetro que este es el problema.
Si usted ve la oscilación, abra la placa de inspección en el amplificador
sección (RFX 75). Compruebe si hay un límite de mylar 1000PF rojo que es
conectado al terminal central del conductor el transistor ERFf 2030 y el
final de transistor de ERF 7530, dirá si este límite se ha instalado.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++
Él quiere que mirar y ver si las partes que ha lo descrito en el correo electrónico están ahí y le hizo saber.
Alos si le ayudará a no es un traductor on-line aquí:
GOOGLE Traducir
73
Jeff
¿Está teniendo problemas para entender el e-mail sólo por el Inglés, o porque no entienden la parte electrónica de la misma?
Aquí está el correo electrónico traducido al español si eso te ayuda.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Buenas tardes
Desde su descripción suena como la radio se está rompiendo en parásitos
oscilación en SSB. Para determinar si la radio va en esta
auto-oscilación, ¿tiene usted un vatímetro de RF que se puede instalar en línea?
Si usted, por favor, poner la línea metro y al soltar el PTT
SSB, si usted ve cualquier lectura sobre el vatímetro a continuación, usted sabe que hay una
oscilación. Además, usted puede confirmar esta girando hacia la izquierda toda la ganancia del micro
de control, si usted ve cualquier lectura sobre el vatímetro que este es el problema.
Si usted ve la oscilación, abra la placa de inspección en el amplificador
sección (RFX 75). Compruebe si hay un límite de mylar 1000PF rojo que es
conectado al terminal central del conductor el transistor ERFf 2030 y el
final de transistor de ERF 7530, dirá si este límite se ha instalado.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++
Él quiere que mirar y ver si las partes que ha lo descrito en el correo electrónico están ahí y le hizo saber.
Alos si le ayudará a no es un traductor on-line aquí:
GOOGLE Traducir
73
Jeff
I got my 257 in Dec, it started smoking as soon as I turned it on. Sent it in for repairs. Now its doing the same thing that AdrianofromBrazil is doing.
Adriano I got an email from Sam Lewis today about your problem, if you can give me your email address I can put you in touch with Sam about your problems, send me your email to tucker4422@verizon.net and I will foward it to Sam Lewis, is is very concerned about your problems
257HP Distorted TX SSB Audio
My 257HP has bad SSB TX audio brand new out of the box. The SSB TX audio sounds distorted and raspy. It sounds alot like RF getting into the modulation. However, I don't think it's an RF problem. Even reducing the RF output to only a few watts still produces the probllem. The SWR into the IMAX 2000 antenna is 1.1 @ 28.450MHz. Swapping in another HF radio into the antenna connection does not have the problem; so that removes the RF as the cause of the problem.
I did a google search on "Magnum 257HP Poor SSB TX audio" and found that I'm not only one having this issue. Some people think the top-gun modulator is the culprit because the previous version of the 257 did not have this problem and the AM TX audio of the 257HP is excellent.
I'm open to any suggestions, otherwise I have no other choice than replacing my 257HP with a different 10 meter rig.
My 257HP has bad SSB TX audio brand new out of the box. The SSB TX audio sounds distorted and raspy. It sounds alot like RF getting into the modulation. However, I don't think it's an RF problem. Even reducing the RF output to only a few watts still produces the probllem. The SWR into the IMAX 2000 antenna is 1.1 @ 28.450MHz. Swapping in another HF radio into the antenna connection does not have the problem; so that removes the RF as the cause of the problem.
I did a google search on "Magnum 257HP Poor SSB TX audio" and found that I'm not only one having this issue. Some people think the top-gun modulator is the culprit because the previous version of the 257 did not have this problem and the AM TX audio of the 257HP is excellent.
I'm open to any suggestions, otherwise I have no other choice than replacing my 257HP with a different 10 meter rig.