Re: Automatic ATU Recommendations?
Hi Richard, The G4TPH loop is very inefficient- up to 10dB worse than loops like the Alex Loop and others. That is why it can handle 100W as opposed to 10W or so with most other loops. 90W is dissipated as heat in all of the aluminum joints and the finger contact in the single gang capacitor. In other words, it requires 100W on 40M to put out the same signal that the Alex Loop would with only 10W. The other clue is that? it is almost 240KHz wide between the 2.62:1 SWR points on 40M. A loop its size should have a 2.62:1 SWR BW of under 20KHz if it were at all efficient. Probably usable on 20M and up but still not efficient as a well designed small TX loop. ? Dale W4OP ?
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From: FT817@... [mailto:FT817@...]
Sent: Wednesday, November 30, 2016 9:23 PM
To: FT817@...
Subject: [FT817] Re: Automatic ATU Recommendations?? ? Thank you, Ray, Bj?rn and Gordo! ? I still have a bit of time before needing the ATU I think, as I have just purchased a ML40HP MK11 Remote Tune Magloop from G4TPH () which I will be using in my loft for now (although I intend to build some of my own aerials later).? I want to get the ATU for use portable next year, especially after I retire at the end of April!? Yes, I think that the T1 is looking the best option at the moment and the Elecraft KX2 is an extremely nice radio too.
73, Richard, G4WKW.
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Re: Automatic ATU Recommendations?
Thank you, Ray, Bj?rn and Gordo! ? I still have a bit of time before needing the ATU I think, as I have just purchased a ML40HP MK11 Remote Tune Magloop from G4TPH () which I will be using in my loft for now (although I intend to build some of my own aerials later).? I want to get the ATU for use portable next year, especially after I retire at the end of April!? Yes, I think that the T1 is looking the best option at the moment and the Elecraft KX2 is an extremely nice radio too.
73, Richard, G4WKW.
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Re: Automatic ATU Recommendations?
At the risk of offering a completely contrary viewpoint, may I suggest not using a tuner but using a resonant antenna instead? Over on your side of the pond, HyEndFed makes some nice multiband band antennas that have worked well with my 817 (and I've got the YouTube videos to prove it :) ).
73 from Tracy VE3TWM.
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Re: Automatic ATU Recommendations?
I have used the Elecraft T1 with my FT-817 during back country canoe trips in Northern Ontario. It has performed very well. Even without the FT-817 control cable it tunes with just a couple of button presses.
There is nothing wrong with the LDG 817 tuner, it is just bigger and heavier than the T1.
The only reason I won't be using my T1 anymore in the backcountry, is because my Elecraft KX2 has the built in ATU, which is also excellent.
Gordon VE3JSJ
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Re: Automatic ATU Recommendations?
The T1 is pricey but super small. I personally love it.
Bj?rn SM7IUN
?
Hi Richard:
I’d go with the Elecraft T1. It’s a great tuner on it’s own, but it also is available with a cable to connect it to the FT-817. That way, when you QSY, the system will remember what the settings were for the last time you used a particular band/frequency.
That said, a log of guys like the LDG unit. The T1 has the benefit of being smaller.
73 de Ray
K2ULR
> On Nov 30, 2016, at 9:09 AM, richard.g4wkw@... [FT817] <FT817@...> wrote:
>
>
>
> I recently joined this awesome group and would be grateful of some advice and recommendations. I renewed my license in the summer after too many years of being inactive and have been concentrating on relearning my CW, building a capacitive touch key and Ardruino-based Keyer. I would like to concentrate on using QRP CW both from home and mobile, often with inadequate antennas, so a good ATU is essential.
>
>
>
> I have an FT-817ND on order and would be very grateful for advice and recommendations for the best ATU to get, which is capable of portable as well as home use. The two I have considered so far are:
>
>
>
> * LDG Z-817 Antenna Tuner.
>
>
>
> * Elecraft T1-A Elecraft 20W Automatic ATU with T1-FT817 Remote Control Adaptor.
>
>
>
> I would very much welcome any thoughts, advice and other suggestions.
>
>
>
> Thank you and 73...
>
> Richard G4WKW
>
>
>
>
>
|
Re: Automatic ATU Recommendations?
Hi Richard:
I’d go with the Elecraft T1. It’s a great tuner on it’s own, but it also is available with a cable to connect it to the FT-817. That way, when you QSY, the system will remember what the settings were for the last time you used a particular band/frequency.
That said, a log of guys like the LDG unit. The T1 has the benefit of being smaller.
73 de Ray
K2ULR
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On Nov 30, 2016, at 9:09 AM, richard.g4wkw@... [FT817] <FT817@...> wrote:
I recently joined this awesome group and would be grateful of some advice and recommendations. I renewed my license in the summer after too many years of being inactive and have been concentrating on relearning my CW, building a capacitive touch key and Ardruino-based Keyer. I would like to concentrate on using QRP CW both from home and mobile, often with inadequate antennas, so a good ATU is essential.
I have an FT-817ND on order and would be very grateful for advice and recommendations for the best ATU to get, which is capable of portable as well as home use. The two I have considered so far are:
* LDG Z-817 Antenna Tuner.
* Elecraft T1-A Elecraft 20W Automatic ATU with T1-FT817 Remote Control Adaptor.
I would very much welcome any thoughts, advice and other suggestions.
Thank you and 73...
Richard G4WKW
|
Re: Automatic ATU Recommendations?
Richard
?
I recommend the Elecraft T1 tuner with the FT-817. I take the combination
everywhere I go, including to Cambodia last year.
?
? With a dipole cut for about 21MHz, I can tune it for 17, 15, and 10
Metres with the ‘T1”, which are my favourite bands for JT-65 digital
communications. But, your needs may be different... it is just convenient, and
works for me!
?
Cheers and 73
Bruce? VK2EM
?
?
|
Re: Tx oscillation on 432 MHz
The paper insert from Yaesu mentions "abnormal operations on 430 Mhz when using an external power supply and the whip antenna, especially with the antenna in close proximity to surrounding metal objects”
The advice is to “wind one turn of the E-DC-6 cable around the supplied ferrite core” and to “install the core as close as possible to the DC plug”
73’s G0UCI
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Automatic ATU Recommendations?
I recently joined this awesome group and would be grateful of some advice and recommendations.? I renewed my license in the summer after too many years of being inactive and have been concentrating on relearning my CW, building a capacitive touch key and Ardruino-based Keyer.? I would like to concentrate on using QRP CW both from home and mobile, often with inadequate antennas, so a good ATU is essential.
I have an FT-817ND on order and would be very grateful for advice and recommendations for the best ATU to get, which is capable of portable as well as home use.? The two I have considered so far are:
* LDG Z-817 Antenna Tuner.
* Elecraft T1-A Elecraft 20W Automatic ATU with T1-FT817 Remote Control Adaptor.
I would very much welcome any thoughts, advice and other suggestions.
Thank you and 73... Richard G4WKW
?
|
Re: Tx oscillation on 432 MHz
If you need the ferrite bead, your radio ?should be modified! The phase reversal is safe for EITHER board, old or new, and increases reliability of the finals, by greatly reducing the tendency to oscillate.-73, KC3VO
Sent from my Verizon Wireless 4G LTE smartphone
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-------- Original message -------- From: "'Robin Gape (lists)' list@... [FT817]" <FT817@...> Date: 11/30/2016 7:45 AM (GMT-05:00) To: FT817@... Subject: Re: [FT817] Tx oscillation on 432 MHz
The mod for an FT-817 PA very clearly written up by Bob, KC3VO,
is to be found in the files section, file name ft-817PAboardmod.pdf
The mod is described for an FT-817 (pre-ND), The 817ND PA uses
different PA FETs, which are rated to be very robust against abuse
(good to 20:1 SWR under specific conditions). The two PA boards
circuit diagrams look to be very similar, except for small changes
in the bias circuitry and some decoupling changes.
The files section of the group is not easy to search. Its content
has grown, to put it at its kindest, beyond the utility of the
Yahoo groups search mechanisms.
Disclosure: I've never experienced the 430MHz misbehaviour
problem, and have no intention, until forced to by necessity, of
applying this mod (or any other) to an otherwise working machine!
73,
Robin, G8DQX
On 30/11/16 01:17, kc3vo kc3vo@...
[FT817] wrote:
?
"You can lead horses to water, but you cannot make them
drink"-- This phrase seems to apply to the 817 group,
since many YEARS ago, I posted a FIX for this oscillation,
to eliminate blown finals, and enable safely leaving
batteries inside, or operation WITHOUT the need for any
"Ferrite Bead"!-All that is required is to disconnect the
miniature coax cable at the input to the final PA board,
and re-connect it afyer swapping shield and center
connector polarity at one end of the cable! NO parts or
adjustments needed! (Be SURE to remove batteries and other
power sources before doing this alteration, and be very
careful not to short or otherwise damage anything) You can
probably find details in the site archives, with photos!
All such oscillations should CEASE after the cable phasing
is reversed!-73, KC3VO
Sent from my
Verizon Wireless 4G LTE smartphone
-------- Original message --------
From: "'Robin Gape (lists)' list@... [FT817]"
<FT817@...>
Date: 11/29/2016 5:34 PM (GMT-05:00)
To: FT817@...
Subject: Re: [FT817] Tx oscillation on 432 MHz
Andrew, and anyone else who never had the documentation or
who lost it,
the original Yaesu note is available, scanned, for
information and fair use:
Hope you find this useful. The official manual notes the
presence of the
ferrite clamp, but fails to tell one what to do with it! The
supplied
split-core clamp is about 31mm long, and 15mm diameter. One
suspects
that any similar clamp will probably do the job.
73,
Robin, G8DQX
On 29/11/16 21:06, andrew73@... [FT817] wrote:
> I don't have any filter - I am the third owner of this
radio and
> although I received it in the original packing box,
only the mike and
> antenna bits were included.? I can buy a snap-on
ferrite choke at an
> electronics shop and will try that.
>
> Thanks
>
> Andrew VK1DA/VK2UH
------------------------------------
Posted by: "Robin Gape (lists)" <list@...>
------------------------------------
And for a great FAQ ( Frequently Asked Questions ) see
Some really good technical info at:
.
Please note that your messages and files sent to this group
may appear anywhere on the Internet or in print without
notice or compensation.
------------------------------------
Yahoo Groups Links
<*> To visit your group on the web, go to:
???
<*> Your email settings:
??? Individual Email | Tr aditional
<*> To change settings online go to:
???
??? (Yahoo! ID required)
<*> To change settings via email:
??? FT817-digest@...
??? FT817-fullfeatured@...
<*> To unsubscribe from this group, send an email to:
??? FT817-unsubscribe@...
<*> Your use of Yahoo Groups is subject to:
???
|
Re: Tx oscillation on 432 MHz
The mod for an FT-817 PA very clearly written up by Bob, KC3VO,
is to be found in the files section, file name ft-817PAboardmod.pdf
The mod is described for an FT-817 (pre-ND), The 817ND PA uses
different PA FETs, which are rated to be very robust against abuse
(good to 20:1 SWR under specific conditions). The two PA boards
circuit diagrams look to be very similar, except for small changes
in the bias circuitry and some decoupling changes.
The files section of the group is not easy to search. Its content
has grown, to put it at its kindest, beyond the utility of the
Yahoo groups search mechanisms.
Disclosure: I've never experienced the 430MHz misbehaviour
problem, and have no intention, until forced to by necessity, of
applying this mod (or any other) to an otherwise working machine!
73,
Robin, G8DQX
On 30/11/16 01:17, kc3vo kc3vo@...
[FT817] wrote:
toggle quoted message
Show quoted text
?
"You can lead horses to water, but you cannot make them
drink"-- This phrase seems to apply to the 817 group,
since many YEARS ago, I posted a FIX for this oscillation,
to eliminate blown finals, and enable safely leaving
batteries inside, or operation WITHOUT the need for any
"Ferrite Bead"!-All that is required is to disconnect the
miniature coax cable at the input to the final PA board,
and re-connect it afyer swapping shield and center
connector polarity at one end of the cable! NO parts or
adjustments needed! (Be SURE to remove batteries and other
power sources before doing this alteration, and be very
careful not to short or otherwise damage anything) You can
probably find details in the site archives, with photos!
All such oscillations should CEASE after the cable phasing
is reversed!-73, KC3VO
Sent from my
Verizon Wireless 4G LTE smartphone
-------- Original message --------
From: "'Robin Gape (lists)' list@... [FT817]"
Date: 11/29/2016 5:34 PM (GMT-05:00)
To: FT817@...
Subject: Re: [FT817] Tx oscillation on 432 MHz
Andrew, and anyone else who never had the documentation or
who lost it,
the original Yaesu note is available, scanned, for
information and fair use:
Hope you find this useful. The official manual notes the
presence of the
ferrite clamp, but fails to tell one what to do with it! The
supplied
split-core clamp is about 31mm long, and 15mm diameter. One
suspects
that any similar clamp will probably do the job.
73,
Robin, G8DQX
On 29/11/16 21:06, andrew73@... [FT817] wrote:
> I don't have any filter - I am the third owner of this
radio and
> although I received it in the original packing box,
only the mike and
> antenna bits were included.? I can buy a snap-on
ferrite choke at an
> electronics shop and will try that.
>
> Thanks
>
> Andrew VK1DA/VK2UH
------------------------------------
Posted by: "Robin Gape (lists)"
------------------------------------
And for a great FAQ ( Frequently Asked Questions ) see
Some really good technical info at:
.
Please note that your messages and files sent to this group
may appear anywhere on the Internet or in print without
notice or compensation.
------------------------------------
Yahoo Groups Links
<*> To visit your group on the web, go to:
???
<*> Your email settings:
??? Individual Email | Tr aditional
<*> To change settings online go to:
???
??? (Yahoo! ID required)
<*> To change settings via email:
??? FT817-digest@...
??? FT817-fullfeatured@...
<*> To unsubscribe from this group, send an email to:
??? FT817-unsubscribe@...
<*> Your use of Yahoo Groups is subject to:
???
|
Re: Tx oscillation on 432 MHz
Thanks very much Robin
73 Andrew VK1DA VK2UH?
|
Re: Tx oscillation on 432 MHz
Thanks so much for letting us know that.
One of the problems with the closed Yahoo group is that the search tools are tricky. ?Once I saw your message, I finally found it in a "Digital Hams.net" forum post, and found that you did the upload on 9July2004
Then I was able to go back to the messages here, and search through the archive, identifying message 36229, where you did your original post.
Then I found the file concerned "https://groups.yahoo.com/neo/groups/FT817/files/ft-817PAboardmod.pdf"
Time to find the modification file - 20 minutes. ?Time to perform the fix, 2 minutes.....
I have now performed the modification, and should be ok into the future.
Horse lead - and drank appropriately.
Doug? VK1ZDJ - Canberra, Australia ?
|
Re: Tx oscillation on 432 MHz
"You can lead horses to water, but you cannot make them drink"-- This phrase seems to apply to the 817 group, since many YEARS ago, I posted a FIX for this oscillation, to eliminate blown finals, and enable safely leaving batteries inside, or operation WITHOUT the need for any "Ferrite Bead"!-All that is required is to disconnect the miniature coax cable at the input to the final PA board, and re-connect it afyer swapping shield and center connector polarity at one end of the cable! NO parts or adjustments needed! (Be SURE to remove batteries and other power sources before doing this alteration, and be very careful not to short or otherwise damage anything) You can probably find details in the site archives, with photos! All such oscillations should CEASE after the cable phasing is reversed!-73, KC3VO
Sent from my Verizon Wireless 4G LTE smartphone
toggle quoted message
Show quoted text
-------- Original message --------
From: "'Robin Gape (lists)' list@... [FT817]" <FT817@...>
Date: 11/29/2016 5:34 PM (GMT-05:00)
To: FT817@...
Subject: Re: [FT817] Tx oscillation on 432 MHz
Andrew, and anyone else who never had the documentation or who lost it,
the original Yaesu note is available, scanned, for information and fair use:
https://www.dropbox.com/s/b9666ds7gsrt7ks/FT-817ND%20Important%20Note%20re%20430MHz%20and%20ferrite%20clamp.pdf?dl=0
Hope you find this useful. The official manual notes the presence of the
ferrite clamp, but fails to tell one what to do with it! The supplied
split-core clamp is about 31mm long, and 15mm diameter. One suspects
that any similar clamp will probably do the job.
73,
Robin, G8DQX
On 29/11/16 21:06, andrew73@... [FT817] wrote:
> I don't have any filter - I am the third owner of this radio and
> although I received it in the original packing box, only the mike and
> antenna bits were included.? I can buy a snap-on ferrite choke at an
> electronics shop and will try that.
>
> Thanks
>
> Andrew VK1DA/VK2UH
------------------------------------
Posted by: "Robin Gape (lists)" <list@...>
------------------------------------
And for a great FAQ ( Frequently Asked Questions ) see http://groups.yahoo.com/group/FT817/database
Some really good technical info at: http://www.ka7oei.com/ft817pg.shtml .
Please note that your messages and files sent to this group may appear anywhere on the Internet or in print without notice or compensation.
------------------------------------
Yahoo Groups Links
<*> To visit your group on the web, go to:
??? http://groups.yahoo.com/group/FT817/
<*> Your email settings:
??? Individual Email | Traditional
<*> To change settings online go to:
??? http://groups.yahoo.com/group/FT817/join
??? (Yahoo! ID required)
<*> To change settings via email:
??? FT817-digest@...
??? FT817-fullfeatured@...
<*> To unsubscribe from this group, send an email to:
??? FT817-unsubscribe@...
<*> Your use of Yahoo Groups is subject to:
??? https://info.yahoo.com/legal/us/yahoo/utos/terms/
|
Re: Tx oscillation on 432 MHz
Andrew, and anyone else who never had the documentation or who lost it,
the original Yaesu note is available, scanned, for information and fair use:
Hope you find this useful. The official manual notes the presence of the ferrite clamp, but fails to tell one what to do with it! The supplied split-core clamp is about 31mm long, and 15mm diameter. One suspects that any similar clamp will probably do the job.
73,
Robin, G8DQX
toggle quoted message
Show quoted text
On 29/11/16 21:06, andrew73@... [FT817] wrote: I don't have any filter - I am the third owner of this radio and although I received it in the original packing box, only the mike and antenna bits were included. I can buy a snap-on ferrite choke at an electronics shop and will try that.
Thanks
Andrew VK1DA/VK2UH
|
Re: Tx oscillation on 432 MHz
Hi,?
When the problem first manifested itself the radio was powered by an internal 3S LIPO (from Windcamp) battery. ?
When retested on the bench it was powered by an external 3S LIPO via the rear DC connector.?
I don't have any filter - I am the third owner of this radio and although I received it in the original packing box, only the mike and antenna bits were included. ?I can buy a snap-on ferrite choke at an electronics shop and will try that.?
Thanks?
Andrew VK1DA/VK2UH? ??
|
Re: FT817 audio mod - PCB pad delamination
Thanks Simon!
After spending some quality time with the service manual I was able to trace Vol 2 (the signal I'm working with) to Pin 49 on J1008 on the main board, as well as a few other points that I can potentially solder to.? I'll be able to take a swing at repairing it once I've located Pin 49 on the board!
Cheers,
John VA7JBE
|
Re: Tx oscillation on 432 MHz
Folks, something to keep in mind… when a PA is replaced, rarely does a tech check every band and mode, while we assume that this is done. I doubt it if anyone checks everything out. I suspect a loose screw or missing ground or oxidation of same. Frank KG9H
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Hi Ken When testing it in the shack, I monitored the output signal on my ic706. ?When it was working ok, the signal was sounding good on all modes. but when the output power went straight to the max level, I could find no signal on the desired frequency or anywhere in the adjacent 100khz or so. To me this indicates that it is not RF feedback, which would present as a howling or noise coming through the standard transmit chain, as an ssb signal. ?There was no such signal, but when it was working, the desired clean signal was there on the right frequency, 432.150 USB. For this reason I guessed that the spurious signal is an oscillation in the final amplifier stage. ?Without a spectrum analyser it is a bit hard to find the spurious unless I get lucky with a scanning receiver. ?I really don't want to run such power on an unknown frequency, certainly not into an antenna.?
I have asked the repairer who installed the new final board whether this fault is a common one in his experience and am waiting for his opinion. ?
Thanks Andrew VK1DA/VK2UH?
|
Re: Tx oscillation on 432 MHz
Hi Ken When testing it in the shack, I monitored the output signal on my ic706. ?When it was working ok, the signal was sounding good on all modes. but when the output power went straight to the max level, I could find no signal on the desired frequency or anywhere in the adjacent 100khz or so. To me this indicates that it is not RF feedback, which would present as a howling or noise coming through the standard transmit chain, as an ssb signal. ?There was no such signal, but when it was working, the desired clean signal was there on the right frequency, 432.150 USB. For this reason I guessed that the spurious signal is an oscillation in the final amplifier stage. ?Without a spectrum analyser it is a bit hard to find the spurious unless I get lucky with a scanning receiver. ?I really don't want to run such power on an unknown frequency, certainly not into an antenna.?
I have asked the repairer who installed the new final board whether this fault is a common one in his experience and am waiting for his opinion. ?
Thanks Andrew VK1DA/VK2UH?
|
Re: Tx oscillation on 432 MHz
I seem to remember a piece of paper in the instruction manual, noting that with your configuration it was sometimes necessary to use a ferrite on the power cable, or mic, or something like that, but I do not have the manual here and cannot remember all the details.
On Monday, November 28, 2016, 6:39 AM, andrew73@... [FT817] wrote:
?
I recently had the final stage of my 817 replaced/upgraded to a new final and I was told the board installed is the same as the ND final.
All looks good on all bands, except that on occasions, the final appears to self oscillate when using 432 MHz, so that pressing PTT and not saying anything, the power output indicator goes full scale. ?
I tested it on a dummy load and got the same behaviour except that I could not get the oscillation if it was set to use the rear antenna connector on that band. ?
Is this a known fault with the 817? ?I searched the archives of the group without finding a direct mention of this problem. ?
Thanks for any insights anyone can offer. ?
Andrew VK1DA
|
Richard G4WKW
Bj?rn SM7IUN
Doug Jackson