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VE3PCD
09-05-2010, 03:49 PM
Hello all !!

Can someone please tell me the correct procedure to tune the FT-101E into the Pulstar AT1KP tuner?

I cant seem to be able to get the swr down, I tune the radio but then unable to get tuner correct the swr....What am I doing wrong?

thx.

Peter

AF6LJ
09-05-2010, 03:59 PM
Hello all !!

Can someone please tell me the correct procedure to tune the FT-101E into the Pulstar AT1KP tuner?

I cant seem to be able to get the swr down, I tune the radio but then unable to get tuner correct the swr....What am I doing wrong?

thx.

Peter

By first tuning the tube radio into a dummy load then tuning the tuner with the radio connected to the tuner.

One of the nice things about some of the MFJ tuners is they have a built in dummy load....
It's just a switch throw away.

KD0CAC
09-05-2010, 04:04 PM
I am posting more to see than answer , but have some idea's .
I found with working a club station how to tune on frequency and not QRM others on that frequency .
Have a antenna analyzer in the circuit with a switch that would be to switch from radio to analyzer , then watch the analyzer while tuning , the tuner on the exact frequency you want to work , now that you have the tuner tuned , turn switch back to radio & tune the radio .

KE3WD
09-05-2010, 04:05 PM
Here is one method, tried and true, with the idea of not getting into territory that can damage output tubes and components in mind:

Use of a 50 ohm Dummy Load and an antenna switch arrangement that allows you to switch between Dummy Load and Antenna Tuner at the Tuner's input can really help.

Tune up the '101 into the Dummy Load first.

Now you have the '101 all set to yield full power into 50 ohms.

Reduce the power of the '101 and switch over to the antenna tuner, and, as rapidly as you can, tune the tuner. It is better to do short transmissions and tune the tuner, stop transmitting for a sec or two and repeat the short tuning transmission picking up where you left off IMO.

Can't stand those !#$&%$ "half hour" tuneups on the bands, and neither can your finals or the components in your tuner.

Writing down the settings for a certain band area so that you can place the tuner controls to those settings when returning is a very good idea. Then you can spend less time in the tuning to get to the optimum point since the controls will already be somewhere near the right places. Some hams place paper stickers at those points on the dials of their tuners (and linear amps) as reference points for the various bands they use, a fine idea for spending less time on the tuneups and more time on the air as well as a good way to have some reference points that would indicate to you any problems that can happen to an antenna system before such can damage components in the tuner - or even the rig itself.

If you don't have a good 50 ohm Dummy Load that can handle the output power of your '101, now is a good time to start thinking about picking one up, along with that antenna switch. Every ham should have a good Dummy Load handy.

KD0CAC
09-05-2010, 04:08 PM
Sue beat me to it .
I have a further question .
If there may be some discrepancies between the dummy load , tuner , feedline and antenna , would the radio tuned into the dummy be a little off ?
Probably close enough though , many ways to skin a cat .

AF6LJ
09-05-2010, 04:24 PM
Sue beat me to it .
I have a further question .
If there may be some discrepancies between the dummy load , tuner , feedline and antenna , would the radio tuned into the dummy be a little off ?
Probably close enough though , many ways to skin a cat .
It wouldn't be off when tuning the tuner for lowest VSWR.

KD0CAC
09-05-2010, 04:47 PM
I was referring to tuning the radio into the dummy load .
But I have not owned or operated a tube radio yet .
Just got two amps , non operational and repairing , a Heathkit SB-201 and a Collins 30L1 .
After getting my ticket , I thought that having to learn ham radio on older rigs would be a better learning experience , because of the solid state rigs turn on and go , instead of what had to be known and set manually with the older rigs ?

AF6LJ
09-05-2010, 04:56 PM
I believe when you have an older tube radio, especially one well metered you do learn more.

AG3Y
09-05-2010, 05:12 PM
A major un-answered question. What mode are you using to tune your setup? Of course, you need to use a continuous carrier to tune the rig, and the auto-tuner needs to see a continuous low level carrier in order to tune for lowest SWR. (probably around 5-10 watts) Are you attempting to tune the antenna tuner with a low-level continuous signal, or are you assuming that you can tune it with a voice signal in SSB ?

That will not work. You MUST use a low level continuous signal!

K0RGR
09-05-2010, 05:30 PM
Yes, back when radios glowed, a dummy load was a fairly essential shack accessory, and this is part of why. A dummy load is the right way. The wrong way is to get the transceiver tuned up well enough to put out a signal that you can use to tune the tuner, then go back and refine the tuning on the transmitter. However, after you've tuned things up a few time, you'll have some idea of what the setting should look like on both the tuner and the transmitter, and you'll be able to get fairly close without much tuning.

It's always a good idea to keep track of your settings for each band, just for this reason. It will also tell you when something changes, which may be an indication of a problem somewhere.

Another option would be to use an SWR analyzer or a noise bridge to tune up the tuner before tuning the transmitter. Noise bridges were also fairly popular in the latter tube days.

WB2WIK
09-05-2010, 05:38 PM
A good dummy load is a ham station essential.

In a pinch, a 1000' spool of RG58 coax makes a pretty good dummy load.

Actually, it makes a great dummy load at VHF!

W0UZR
09-05-2010, 05:43 PM
If you don't have a dummy load, then turn the CARRIER down to where you have just 100 milliamps on transmit. Then tune the Plate and Load over and over for best output while keeping it at 100 milliamps. Then key up and tune the tuner for lowest SWR. After you get the best SWR on the tuner, then increase the drive and tune the radio and retune the tuner.

OK, NOW, if you are unable to tune the tuner after all that for lowest SWR then two things might be happening.....

1. Your SWR is way too high and the antenna needs to be worked on to get it down. And if that is not the case then

2. When you tune one knob on the tuner for lowest, then go past the dip turning the knob in the same direction, and the SWR will go higher, and tune the other knob and see if it will drop further. If it does, then go further turning that knob in the same direction and the SWR will read higher, then retune the first knob again and it should drop again and by this time it should be close to flat. This is what I have to to with my Drake Tuner to get it flat.

And if tuning further in the same direction letting the SWR go back up does not work, and tuning the other knob doesn't make it go down more, then turn the knob in the oppisit direction which should be BEFORE YOU GET TO THE DIP, where the SWR goes back up some, and then tune the other knob, and go past the dip and let the SWR rise some and then retune the first knob again and it should drop a quite a bit more.

This doesn't sound like it's right, but with this meter I have, that's the only way I can get mine tuned. It might be the same with yours.

W5HTW
09-05-2010, 07:13 PM
Being sure you know this - those final tubes in the FT101E are very easily destroyed and very expensive to replace. Tuning ten seconds out of resonance will probably arc one or both over. Then you will have to spend $100 to buy a new pair.

That said, we'll address the question. First, if your tuner has a built in dummy load, use it.

Preset the controls to the right frequency, which includes the Plate and Loading controls and the preselector.

Turn the Drive/carrier all the way down. Zero.

Switch to TUNE. Or, to CW if you have a key. But Tune will work.

Slowly increase the Carrier control until the plate current (be sure you are monitoring plate current, and not RF output) goes up a little.

I always set the radio's Load control to minimum, but setting it at the 50 ohm spot is ok.

Now rotate the Plate control for a dip.

When you have the dip, increase the Drive/Carrier control to get perhaps 100 ma plate current on the meter. (That is Ip, by the way.)

Now be sure you have a noticeable dip by rotating the Plate control each direction just slightly and be sure plate current rises.

Increase the Load control to the preset position.

Pause. Switch to receive and let the finals cool a good 30 seconds.

Switch back to TUNE and start increasing the carrier control until you get about 150 ma on the plate meter.

Recheck the dip. It should still be good.

You are tuned up. Switch to receive and let the tubes cool.

Now switch the tuner in line. You can rotate those controls for maximum received noise and be fairly close.

Set the tuner's meter switch to SWR or Reflected, however it is worded.

Once again, reduce the Carrier control on the FT101, but not all the way.

Switch to Tune (or CW) again, and rotate the "transmitter" control on the tuner for minimum reading. Watch the plate current meter on the 101 so the current does not rise above 150 ma.

I don't know your tuner. If it has a roller inductor, you can also tune that for minimum SWR as well as the Antenna control. Make adjustments as quickly as you can, and keep plate current below 150 ma by reducing the Drive/Carrier.

This should get you there.

Some tuners will not reduce SWR to anywhere near zero, depending upon the antenna being used. Wide range manual tuners may tune 30 to 1200 ohms reactance, but there are many that will not cover that range.

Most of us who use tube type radios regularly actually used them by necessity 'back in the day' so the Plug and Play radios weren't available. We were forced to learn. Amateurs today have not had that requirement, so when they try a tube output radio, including an amp, they are often lost. In those cases, they should try to find a local ham with experience in tube transmitters, to give them some hands-on training. This is especially true with transmitters or transceivers using sweep tube ouput stages, as those tubes arc very easily, self destructing in a couple of seconds.

Another factor is so many of the FT101's were 'CB-ized." Driven very hard and put up wet. It was one of the most popular illegal 'CB' rigs around, and many thousands never saw a ham band. That resulted in tremendous strain on the final compartment, and often the driver as well. Many of them were run at well over the 40 watts AM (Input, not output!) at which they were rated, with incredible final dissipation.

I was fortunate to have a couple of FT101E's (one was an EE) that had never been run on CB, so operating them within their factor parameters made them highly reliable, even with the old sweep tubes.

Oh yes! Be SURE you have the manual, you read it, and understand it. It can be downloaded at several places. Don't operate the rig without reading the manual!

Good luck with yours

Ed

KD7MSC
09-05-2010, 07:17 PM
A good dummy load is a ham station essential.

In a pinch, a 1000' spool of RG58 coax makes a pretty good dummy load.

Actually, it makes a great dummy load at VHF!

I have used a 100 watt light bulb in a pinch (and just for fun too).

VE3PCD
09-05-2010, 07:25 PM
I want to say thank you to all who responded, I am not really surprise how many good responses I received. The main reason why I decided to get the FT-101E is that it will allow me to experience what it was like years ago when tube radios ruled the HAM universe. I am now able to properly tune my rig.

73,

Peter

AF6LJ
09-05-2010, 07:30 PM
I knew someone who had an FT-101 wish I had one.

NO2A
09-05-2010, 08:44 PM
I`m sure there`s one waiting for you on e-bay............................:p
I knew someone who had an FT-101 wish I had one.

W8JI
09-05-2010, 08:59 PM
Assuming you have a tuner and a high SWR on the antenna system without the tuner, it is imperitive you tune the FT101 into a good dummy load as a first step.

A light bulb will not work.

Here are the steps:

1.) Load the Ft101 into a dummy load that you know is 50 ohms.

2.) Reduce the power until it is down to the minimum amount that allows you to adjust the tuner. The amount of power depends on the tuner and the meter in the tuner.

3.) Adjust the tuner for minimum SWR.

4.) Increase power without retuning the radio, and make sure the reflected power is minimum.

That should be all you need to do.

73 Tom

KL7AJ
09-06-2010, 03:35 AM
Hello all !!

Can someone please tell me the correct procedure to tune the FT-101E into the Pulstar AT1KP tuner?

I cant seem to be able to get the swr down, I tune the radio but then unable to get tuner correct the swr....What am I doing wrong?

thx.

Peter

I'd just tune the tuner for maximum receive noise, and then tune the transceiver as if you were tuning directly into a dummy load. Close enough for government work.

Eric

W8JI
09-06-2010, 08:40 PM
I'd just tune the tuner for maximum receive noise, and then tune the transceiver as if you were tuning directly into a dummy load. Close enough for government work.

Eric

I don't think so Eric. That might result in a 2:1 SWR or even higher.

Better he does things the right way, and adjusted the radio into a 50 ohm load. Then he can reduce power and adjust the tuner properly for lowest SWR.

K9YLI
09-06-2010, 09:23 PM
Well no one has brought up the use of Pi-net out put tube type radios.

The PI-net would tune most antennas just fine..

In other words, 'back in the day' with tube type out put radios,
there were no "tuners" , no need for them..

just hook up the antenna, dip and load and drive, repeat, repeat , repeat..
My Galaxy GT550 or my old Gonset G76 AM rig, no tuners needed, they just confuse the Pi-net output.

If you antenna is a reasonable one, tuning into a dummy load and marking the controls, usually the antenna will be close to those settings.
speeds up the tune up process..

WD9GYF
09-07-2010, 12:05 PM
I knew someone who had an FT-101 wish I had one.

I have a 101EE along with the 2 & 6 meter transverters, Sp101PB phone patch, FV 101B Ext. VFO, FL 2100B Amp,YC601 Didgital Display, still looking
for the YO 100 Scope. One comes up every so-often on E-Bay:D


Jim
WD9GYF/5

AF6LJ
09-07-2010, 12:53 PM
I have a 101EE along with the 2 & 6 meter transverters, Sp101PB phone patch, FV 101B Ext. VFO, FL 2100B Amp,YC601 Didgital Display, still looking
for the YO 100 Scope. One comes up every so-often on E-Bay:D


Jim
WD9GYF/5
Nice looking gear and as I remember the FT101 worked rather well.

KJ4LCM
09-07-2010, 01:19 PM
Hello all !!

Can someone please tell me the correct procedure to tune the FT-101E into the Pulstar AT1KP tuner?

I cant seem to be able to get the swr down, I tune the radio but then unable to get tuner correct the swr....What am I doing wrong?

thx.

Peter

You don't! You don't need a tuner with those radios, the tank circuit is its own tuner and will happily match a wide range of antennas. If it won't match well, you need antenna work first.

VA3CQC
09-07-2010, 02:14 PM
I think he was asking more how to go from the "tuned 50ohms into dummy load" to "tuned Xohms into antenna". I think the question's been answered, but I see no one's covered the benefits of having an actual roller-inductor tuner! It's even a differential-T tuner, those cost a bundle. Never used one myself, but I see the theory of how it operates, and it should be the same as an L-network.

You begin with the transmitter emitting 100w at the correct plate current into a 50 ohms dummy load, then you REDUCE the drive, back to zero. Turn the tuner's antenna switch to your antenna, and reduce the capacitor to zero. Scroll through the inductor starting at zero, (but be careful, roller inductors get some serious inertia going, so avoid banging them against the stops) and listen for a peak in noise/signal, this could be a point of low SWR. Find the middle of the peak with the inductor, and key up in TUNE as you raise the power. Note the SWR. Then INCREASE the capacitor and see IF/HOW the peak in the noise/signal changes, it will require you to move the inductor one way or another, and the peak will have gotten sharper, or diminished, this is usually inversely proportional to the SWR. If you key the transmitter again on this peak, you'll see the SWR has gotten better. The key is to aim for a high capacitor setting and a low inductor setting. Problem is, there is a minimum inductance you must use for each band, so you start with zero, and work your way up the inductor. This is my understanding of it.

VA3CQC
09-07-2010, 02:19 PM
You don't! You don't need a tuner with those radios, the tank circuit is its own tuner and will happily match a wide range of antennas. If it won't match well, you need antenna work first.

I hear this is actually incorrect. If you try this, the PA produces spurious RF and harmonics. Its ratings are only valid when the output impedance is tuned to 50 ohms, otherwise it "self-tunes" onto a random frequency. The Pi-network in this case acts as a lowpass filter and not a tuner. The instructions usually warn against this, though the transmitter may be capable of matching different resistive loads it is not capable of matching reactive loads.

AI3V
09-07-2010, 02:30 PM
There is only one way to tune a transmitter.

Tuning for maximum power is NOT that way.

Try this- Tune the transmitter for rated DC input AT THE RESONANCE DIP.

Let the output network do it's job- transforming the antenna system impedance to the impedance the tube "wants" to see.

This is the REASON for the plate/cathode current meter.

If you still do not have enough range on the output network- the usual symptom is running out of load adjustment before you reach RATED DC INPUT TO THE FINAL- then re tune into a dummy load, and then adjust the "tuner" for minimum VSWR.

Or you can twist the knobs in a random fashion, and hope to find a acorn.

Rege

KM3F
09-07-2010, 08:17 PM
I agree with the dummy load use,as well.
I tune into the dummy load thru the bypass switch in my old Heathkit SA2060.
Then back to the antenna I want to use.
Adjust for the least inductunce and most input and output capacity the tuner settings will alow and get the match below 1.5 to 1.
If you have a power meter inline between the radio and the tuner, it should show the max power the radio will offer when the load it sees is 50 ohms +/- a small amount..
A power meter inline after the tuner may show the power as greater or less depending on it's accuracy and if the SWR presented by the feedline is inductive or capacitive.
Also not much thought about, the tuner will have some loss of power on thru-put depending on it's setting and just it's normal losses.
Note that the SWR on the feedline will still be there no mater what setting the tuner is at because that will not change much, if at all.
As an end result, you still do not correct the SWR at the antenna but may affect it to some degree by what the tuner reflects back to the antenna.
The tuner only makes the match between the radio and what the tuner sees from the connecting coax.
.
It will take some time and should be an education; but take the time to run each band's settings and record them.
When going to that band, use the setting again and you will be very close with only a touchup when matching a frequency above or below the settings you begin from.
It shortens the time you transmit a signal trying to adjust the tuner.
Just hit the match somewhere at 1.5 or less and not try to get it flat and your good to go.
BTW, I hear much to often someone tunes up right on a frequency being used and causes QRM. Please don't do this. Go off at least 3 kc and even then you may not hear others if the propagation is one way.Those who do it will cause a tone to the others and may cover up a transmitting station with your tune signal.

VE3FMC
09-07-2010, 10:45 PM
Hello all !!

Can someone please tell me the correct procedure to tune the FT-101E into the Pulstar AT1KP tuner?

I cant seem to be able to get the swr down, I tune the radio but then unable to get tuner correct the swr....What am I doing wrong?

thx.

Peter

Now that you know how to tune everything up please invest in a dummy load. It saves spewing unwanted QRM on the bands.

BTW, if you are using a multiband antenna such as a G5RV here is a valuable tip.

On every band, and on the frequencies you will use the most write down the tuner settings.

Make a little chart and keep it right in front of your tuner at all times.

That way you can QSY from 7.200 to 3.755 and change the tuner settings to what you have written down.

Then tune that FT-101E (nice old rig, I have one here) into the dummy load. After that you can quickly tune the tuner up for lowest SWR as you are pretty close to begin with. That is why you need to write down the tuner settings for the areas of the bands you use the most.

Makes tuning up a lot quicker and easier.

KJ4LCM
09-08-2010, 12:44 PM
I hear this is actually incorrect. If you try this, the PA produces spurious RF and harmonics. Its ratings are only valid when the output impedance is tuned to 50 ohms, otherwise it "self-tunes" onto a random frequency. The Pi-network in this case acts as a lowpass filter and not a tuner. The instructions usually warn against this, though the transmitter may be capable of matching different resistive loads it is not capable of matching reactive loads.


Well then,

You heard wrong!

VE3PCD
09-08-2010, 11:46 PM
Thanks to all I am now able to properly tune this baby,

btw, I do have a dummy load (the 2nd I bout after by radio)

Thanks, 73
Peter


Now that you know how to tune everything up please invest in a dummy load. It saves spewing unwanted QRM on the bands.

BTW, if you are using a multiband antenna such as a G5RV here is a valuable tip.

On every band, and on the frequencies you will use the most write down the tuner settings.

Make a little chart and keep it right in front of your tuner at all times.

That way you can QSY from 7.200 to 3.755 and change the tuner settings to what you have written down.

Then tune that FT-101E (nice old rig, I have one here) into the dummy load. After that you can quickly tune the tuner up for lowest SWR as you are pretty close to begin with. That is why you need to write down the tuner settings for the areas of the bands you use the most.

Makes tuning up a lot quicker and easier.

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