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MAGNUM 257 HP Review
- Thread starter Robb
- Start date
Yes, and I mentioned to read the manual - which I included in the review in a .pdf file.
The drywall inserts make for a cool solution to putting a fan on any radio with a heat sink.
Nice tip - and much appreciated too!
The drywall inserts make for a cool solution to putting a fan on any radio with a heat sink.
Nice tip - and much appreciated too!
I did the same and a few other things including rewraping the power filter and the wire to the rfx w/grd with larger wire. More just for good will. It did give it a little more on the 43.
Add a fan to the heatsink...
Add a fan to the heatsink is an idea some locals have done with a small amount cash and effort. If you do go this route, get a fan that is very quiet, and can be had at a computer shop -or even out of an old computer. It will need to be the same size as the heatsink as well.
Secure it to the heatsink with some plastic drywall inserts. One can either wire it to the power in on the board - or even to the power from the on/off switch.
Better to have a heat sink fan on this radio - than not. It is an easy install that will pay the benefit of keeping the output transistors running as cool as possible. And keep the power turned down to the prescribed 75 watts or less!
Add a fan to the heatsink is an idea some locals have done with a small amount cash and effort. If you do go this route, get a fan that is very quiet, and can be had at a computer shop -or even out of an old computer. It will need to be the same size as the heatsink as well.
Secure it to the heatsink with some plastic drywall inserts. One can either wire it to the power in on the board - or even to the power from the on/off switch.
Better to have a heat sink fan on this radio - than not. It is an easy install that will pay the benefit of keeping the output transistors running as cool as possible. And keep the power turned down to the prescribed 75 watts or less!
Power adjustment
I could do with a little help here..
I read the review of this radio and purchased one..thanks for the review, it was good. I have owned HTX-10's before and they were good but they don't make them anymore. Thanks Magnum for a great radio!
I looked at VR16 for AM adjustment because the AM on my radio was very low (4 amp draw max). I adjusted VR16 and found that it adjusted the power output for everything. I don't mind this at all but I see this is not the same for the htx-10 or the magnum 257, only the HP does this?
Now the radio draws 6 amps AM and FM and 11 amps SSB and power out put appears to be 50 watts AM and FM and 100 watts SSB.
I would like to add, I cannot turn the power down to below 40 watts either, and all of this was just the result of adjusting VR16... nothing else. I would like to be able to turn it down to less than 40 watts but it's no big deal.
Thanks for any help, information or comments you may have.
I could do with a little help here..
I read the review of this radio and purchased one..thanks for the review, it was good. I have owned HTX-10's before and they were good but they don't make them anymore. Thanks Magnum for a great radio!
I looked at VR16 for AM adjustment because the AM on my radio was very low (4 amp draw max). I adjusted VR16 and found that it adjusted the power output for everything. I don't mind this at all but I see this is not the same for the htx-10 or the magnum 257, only the HP does this?
Now the radio draws 6 amps AM and FM and 11 amps SSB and power out put appears to be 50 watts AM and FM and 100 watts SSB.
I would like to add, I cannot turn the power down to below 40 watts either, and all of this was just the result of adjusting VR16... nothing else. I would like to be able to turn it down to less than 40 watts but it's no big deal.
Thanks for any help, information or comments you may have.
M257HP
Its not going to last long at 100w. Look at the size of the heatsink and back it off before you cook it. The transistors may be able to run red hot but the little bits around them can't and when they go poof so does the final...
Try turning up the internal mic gain pot instead....
Its not going to last long at 100w. Look at the size of the heatsink and back it off before you cook it. The transistors may be able to run red hot but the little bits around them can't and when they go poof so does the final...
Try turning up the internal mic gain pot instead....
PEP is 100 watts sideband with a tone and RF set to 100%. Most of the time it does not exceed 50 or so watts because I set RF output at about 50%. On sideband I can turn the modulation down to nothing and there is no power output.
It's the 50 watts AM and FM I don't understand.. I only adjusted VR16, AM nothing else.
I can always replace the RFX 75 unit if it goes but I just ordered a fan so that will help.
I am getting very good audio reports with this radio.
Thanks for the comment.
This is a great thread for me, the newcomer. I am about to buy my first rig and the 257HP was near the top of my list. I have read every single post in this thread and I'm still on-the-fence.
Even though I have a full size pickup (2006 Tundra), space is really an issue for mounting a radio - possibly a swivel mount on the center console.
If anyone wants to throw some advice my way, I would greatly appreciate it. My requirements are:
Small size
AM / SSB
Auto Frequency Scan
Higher Power
Easy to use (while driving) controls
Don't need audio toys at all.
I passed my Tech FCC license on Sept 1 - not that it matters for this application. We are traveling across country next year and I need the radio for local road talk.
Cheers and thanks.
Even though I have a full size pickup (2006 Tundra), space is really an issue for mounting a radio - possibly a swivel mount on the center console.
If anyone wants to throw some advice my way, I would greatly appreciate it. My requirements are:
Small size
AM / SSB
Auto Frequency Scan
Higher Power
Easy to use (while driving) controls
Don't need audio toys at all.
I passed my Tech FCC license on Sept 1 - not that it matters for this application. We are traveling across country next year and I need the radio for local road talk.
Cheers and thanks.
If you have a tech license you can operate a 10 meter radio from 28.300 to 28.500 USB and talk all over the world. For the last couple of days 10 meters has been open to Australia and Hawaii etc.
For local communications I like Unidens. The classic style like these.
GI JOES CB RADIO - UNIDEN CB RADIO - UNIDEN CB RADIOS
You just don't need anymore than 4 or 5 watts for local chit chat. In fact you can talk all over the world on 5 watts on 10 meters when conditions are right. Even now, with low sunspot conditions there are beacon reports from all over the world on 10 meters and most beacons are 5 watts.
Thanks 10M.
I was looking at having both 10M and 11M capability by grabbing a 257HP. If I read correctly, you just set jumper "con3" and you have both bands.
Don't know about mobile antenna tuning though. Was hoping to use the same Wilson 1000 for 10 and 11 meters.
I actually got my General Class Amateur license when I was 13-years old (about 120 years ago!). So, going back and getting a tech license is like re-living my lost youth. Anyway, I have forgotten much and so much is new.
Don't mean to step on this thread with my agenda. I am just interested in the 257HP.
Cheers.
I was looking at having both 10M and 11M capability by grabbing a 257HP. If I read correctly, you just set jumper "con3" and you have both bands.
Don't know about mobile antenna tuning though. Was hoping to use the same Wilson 1000 for 10 and 11 meters.
I actually got my General Class Amateur license when I was 13-years old (about 120 years ago!). So, going back and getting a tech license is like re-living my lost youth. Anyway, I have forgotten much and so much is new.
Don't mean to step on this thread with my agenda. I am just interested in the 257HP.
Cheers.
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I don't know if you could find a mobile antenna with that much bandwidth anyway.
I use a big tri-mag mount and cb antenna cut for the middle of 10m, it covers all of 10 meters that way. I would think it would have a very high swr on cb frequencies. But good for monitoring I would think. I had to cut 6 inches off the antenna for 10m, so there is no way it would work on cb now.
I saw a little mag mount cb antenna in walmart, I bet it would work great for local stuff on the highway. It was 12 bucks. That and a Uniden with weather channels.
I don't know if you could find a mobile antenna with that much bandwidth anyway.
I use a big tri-mag mount and cb antenna cut for the middle of 10m, it covers all of 10 meters that way. I would think it would have a very high swr on cb frequencies. But good for monitoring I would think. I had to cut 6 inches off the antenna for 10m, so there is no way it would work on cb now.
I saw a little mag mount cb antenna in walmart, I bet it would work great for local stuff on the highway. It was 12 bucks. That and a Uniden with weather channels.
As far as the mobile antenna with broad bandwith, Right now i use a Bronco buster ( copy of a 10k ) made by Monkey Made with round coils. On Freq. 26.185 1.6 SWR on 27.185 1.1 on SWR. I am going to try the 10k Preditor that some members were talking about and see how the bandwith on that antenna is. And i am running Freq's below Ch.1 11m. I have not tried to reset antenna for 10m use. I do not do into 10m. JMHO
Robb thank you so much for this review. Right now i am switching from the RCI-2970n2 to the RCI-2950dx to run in my work van. But my mind is on the 275hp for a base.