Get the Icom 7300 to Tune Past 1:3
Created by on 2019-12-28Hi there,
As you know most transceivers will not tune above 1:3 when the internal ATU is used.
If you happen to own an Icom7300 and the firmware is updated to one of the latest like 1.30.
Then you can make it tune 1:10+ without any problems at all.
The manual states it will not do 100W anymore, but that is just AM/FM...who cares?
What you need to do is put the transceiver in EMERGENCY MODE! What???
Yes you read it right, EMERGENCY MODE...at it will reduce power to 50-Watts average...
Hang on? Average? Yes...but for SSB the Icom is also just doing 100-Watts...right, so it tunes the same but will take 1:10+
How do you do this?
Menu -> Set -> Others -> Emergency -> Tuner -> {{Restart-to-set}}
After restarting it will show an Orange-E
It tells you it's just doing 50-Watts, but in fact the peaks are still there.
Normal 100-Watts PEP SSB modulation is about 25-Watts anyway, nobody will notice at all but you as your antenna tunes fine.
| KD5MXA | 2020-02-11 | |
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| Get the Icom 7300 to Tune Past 1:3 | ||
| I’ve only had my 7300 since last week and I tested this today on my 106’ doublet. Wow! It worked on all the bands I tested on - 75, 40, 20 and 17. Conditions weren’t great But I had QSOs on 40 and 20. I have a manual tuner but that’s a bit of a pain. I was looking for an auto tuner but I’m not so sure I need one now. | ||
| KT0DD | 2020-01-15 | |
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| Get the Icom 7300 to Tune Past 1:3 | ||
| Ten Tec still has the best internal factory tuners in their Omni 7+ and Eagle 599. They say they are rated for a 10:1 matching capacity right out of the box. No special setting or power reduction needed. I wish Yaewoodcom would follow suit. Too bad Ten Tec is dying a slow death from apathy by it's current owner. I am interested in the Eagle 599 mobile radio but when I emailed Ten Tec they replied they are sold out of the eagle and the next production run is yet to be determined. ( which really means it's been discontinued.) The only radio available from them now is the Omni 7+ and I suspect that's only while supplies last. They seem to only care about commercial sales now. Anyway, enough of my soapbox. Todd - KT0DD | ||
| KD7MW | 2020-01-11 | |
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| Re: Get the Icom 7300 to Tune Past 1:3 | ||
| The article’s author is European. He expressed SWR in the reverse order from how we do it in the US. This seemed obvious to me, as he did it consistently throughout the article. He is saying that the IC-7300, in normal operating mode, can only match antennas with SWRs of 3:1 or less with its internal tuner. But put the 7300 into 50 watt “Emergency Mode,” and it can match an SWR of up to 10:1. This is a very useful feature. It is documented in the 7300’s advanced manual. Reply to a comment by : W4KVW on 2020-01-07 Are you talking about a 1.3.1 SWR? If that is so & that is all the SWR that you have why would you worry about tuning it? Nobody should ever see or hear the difference in a signal with a 1.3.1 from a 1.1.1 SWR.The story is not very plain but maybe it's something only those with an ICOM 7300 would understand? Also if an internal tuner can't handle more than a 1.3.1 SWR it's pretty much Useless.Most internal tuners usually handle a 3.1 SWR with ease but that's about it I think. Clayton W4KVW | ||
| N0GV | 2020-01-11 | |
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| Re: Get the Icom 7300 to Tune Past 1:3 | ||
| Just an error in the posting from K6AER - 1. Overvoltage protection isn't required IF the load (antenna) is tuned. The finals only see the equivalent of the designed for load of 50 ohms through their matching network. 2. A 150 Ohm load will, in theory, have a VSWR of 3:1 but the reflected voltage is 2/3 of the forward voltage giving a 1.67 X voltage peak on the transmitter's output. A 16.7 Ohm load will, in fact, increase the current. I am presuming a very short length of line between the load and the transmitter (source). Obviously a 90 degree long line (quarter wave) makes a short look like an open and vice versa. Bottom line, the limited tuning range is likely more a result of the binary switching in and out of inductors and capacitors in the tuner in modern radios and the limitations on the tuner capacitor voltages as the internal voltages can be quite high if the tuner has a decent Q. An internal Q of 10 will effectively multiply voltage/current by 10 so a 100 watt rms signal of 70.7 V rms will, internally to the tuner, go as high as 700 Volts! Likewise the internal currents can become extreme in the same manner leading to all sorts of interesting non-linear effects in the inductor cores when they saturate. Loads of toasty warm heat, harmonic generation and intermod generation can and does occur in these circumstances. The older stepper motor/servomotor driven air/vacuum variable capacitors and air core inductors were way more forgiving... and expensive/slow. Sincerely, Grover Larkins Reply to a comment by : K6AER on 2020-01-10 Your statement on the maximum VSWR a 7300 can handle is backwards it should read 3:1. This gives the 7300 a tuning range of 16 to 150 ohms in reference to 50 ohms. What manufactures are trying to is preserve the finals from excessive voltage in the output PA stage. When encountering a 10:1 VSWR the power has to be limited in order for the output transistors not suffer a voltage breakdown failure. A 10 to one ratio would be impedances from 5 to 500 ohms. | ||
| K6AER | 2020-01-10 | |
|---|---|---|
| Get the Icom 7300 to Tune Past 1:3 | ||
| Your statement on the maximum VSWR a 7300 can handle is backwards it should read 3:1. This gives the 7300 a tuning range of 16 to 150 ohms in reference to 50 ohms. What manufactures are trying to is preserve the finals from excessive voltage in the output PA stage. When encountering a 10:1 VSWR the power has to be limited in order for the output transistors not suffer a voltage breakdown failure. A 10 to one ratio would be impedances from 5 to 500 ohms. | ||
| AF5CC | 2020-01-10 | |
|---|---|---|
| Re: Get the Icom 7300 to Tune Past 1:3 | ||
| The older rigs from the 80s and early 90s would have internal tuners that would tune about anything, well above a 10:1 SWR. I wish they were still putting those tuners in the new radios. Reply to a comment by : W4KVW on 2020-01-07 Are you talking about a 1.3.1 SWR? If that is so & that is all the SWR that you have why would you worry about tuning it? Nobody should ever see or hear the difference in a signal with a 1.3.1 from a 1.1.1 SWR.The story is not very plain but maybe it's something only those with an ICOM 7300 would understand? Also if an internal tuner can't handle more than a 1.3.1 SWR it's pretty much Useless.Most internal tuners usually handle a 3.1 SWR with ease but that's about it I think. Clayton W4KVW | ||
| KF5HWG | 2020-01-10 | |
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| Get the Icom 7300 to Tune Past 1:3 | ||
| That's a great tip for 7300 owners and makes the rig even more attractive since you can skip a external tuner. If the antenna is worse than 10:1 you probably need to work on the antenna. Thanks for the tip???? | ||
| W4KVW | 2020-01-07 | |
|---|---|---|
| Get the Icom 7300 to Tune Past 1:3 | ||
| Are you talking about a 1.3.1 SWR? If that is so & that is all the SWR that you have why would you worry about tuning it? Nobody should ever see or hear the difference in a signal with a 1.3.1 from a 1.1.1 SWR.The story is not very plain but maybe it's something only those with an ICOM 7300 would understand? Also if an internal tuner can't handle more than a 1.3.1 SWR it's pretty much Useless.Most internal tuners usually handle a 3.1 SWR with ease but that's about it I think. Clayton W4KVW | ||
