I think pretty much any diode can be used as a varactor. Some are just better than others. 73 -Jim NU0C On Sun, 23 Jun 2024 07:45:50 -0700 "A. John Hecht via groups.io" <k6koi@...> wrote: Emerson, do those diodes function as vari-caps?
On Jun 22, 2024, at 7:18?PM, Emerson PP6EW via groups.io <bunhoel@...> wrote:
John
I guess you can replace the varicap by a 1N4001 -1n4007.
Emerson
PP6EW
|
Emerson, do those diodes function as vari-caps? ?
toggle quoted message
Show quoted text
On Jun 22, 2024, at 7:18?PM, Emerson PP6EW via groups.io <bunhoel@...> wrote:
John
I guess you can replace the varicap by a 1N4001 -1n4007.
Emerson PP6EW
Em sáb., 22 de jun. de 2024 às 20:34, A. John Hecht via <k6koi= [email protected]> escreveu: I recently was given two FT101ZD's, one a "Parts rig" Mark I and the other a Mark II.? Both required work but both are now working.? I found I had to remove the voltage to PIN 2 of the VFO input connector to calm down the VFO in the Mark I. The VFO was moving like crazy and when it did settle down it still had an issue with warble.? Removing the voltage solved the issue but now of course the Clarifier function is no longer.? It appears that the variable-cap diode (D01) for the clarifier circuit is defective.? I have some of those diodes on order from China so I'll know soon enough after they arrive.? Has anyone else had an issue with this vari-cap diode??
|
Thank you Jim for taking the time to respond to my posting. I agree that a DMM would not detect a very slight voltage variation in the DC, especially if the sampling rate of the DMM is too slow. And even with a scope it would be a challenge to see ripple without very careful adjustment of triggering, etc. So to check the voltage I substituted battery. The warble returned with that voltage. I really think it’s the var-cap diode. We’ll see. I might just leave the voltage off pin 2 of the 4 pin to the VFO and claim success! (Not an elegant solution.)
BTW, I also agree that connectors are always suspect in these old rigs. In fact some of the Molex connectors were I did use De-Oxit on the connectors to and from the VFO.
toggle quoted message
Show quoted text
On Jun 22, 2024, at 8:35?PM, Jim Shorney via groups.io <jimNU0C@...> wrote:
I recently repaired a FT-707 that had, among other things, clarifier issues. I found that the JFET constant current source and the Zener diode in the clarifier power circuit to be bad. Not flakey, hard failures. The clarifier voltage source must be absolutely stable. More stable that what you can see on the average DMM. After all that the clarifier frequency was lagging behind the action of the knob. It sounded like a capacitive charge curve. I checked EVERYTHING in and around the VFO and clarifier. Including the varactor. It was driving me nuts. It turned out to be the stupid connector that plugs into the VFO.
Check the simple stuff first.
73
-Jim (I hope I never see that radio again)
NU0C
On Sat, 22 Jun 2024 15:10:00 -0700
"A. John Hecht via groups.io" <k6koi@...> wrote:
I recently was given two FT101ZD's, one a "Parts rig" Mark I and the other a Mark II. Both required work but both are now working. I found I had to remove the voltage to PIN 2 of the VFO input connector to calm down the VFO in the Mark I. The VFO was moving like crazy and when it did settle down it still had an issue with warble. Removing the voltage solved the issue but now of course the Clarifier function is no longer. It appears that the variable-cap diode (D01) for the clarifier circuit is defective. I have some of those diodes on order from China so I'll know soon enough after they arrive. Has anyone else had an issue with this vari-cap diode?
|
I recently repaired a FT-707 that had, among other things, clarifier issues. I found that the JFET constant current source and the Zener diode in the clarifier power circuit to be bad. Not flakey, hard failures. The clarifier voltage source must be absolutely stable. More stable that what you can see on the average DMM. After all that the clarifier frequency was lagging behind the action of the knob. It sounded like a capacitive charge curve. I checked EVERYTHING in and around the VFO and clarifier. Including the varactor. It was driving me nuts. It turned out to be the stupid connector that plugs into the VFO. Check the simple stuff first. 73 -Jim (I hope I never see that radio again) NU0C On Sat, 22 Jun 2024 15:10:00 -0700 "A. John Hecht via groups.io" <k6koi@...> wrote: I recently was given two FT101ZD's, one a "Parts rig" Mark I and the other a Mark II. ?Both required work but both are now working. ?I found I had to remove the voltage to PIN 2 of the VFO input connector to calm down the VFO in the Mark I. The VFO was moving like crazy and when it did settle down it still had an issue with warble. ?Removing the voltage solved the issue but now of course the Clarifier function is no longer. ?It appears that the variable-cap diode (D01) for the clarifier circuit is defective. ?I have some of those diodes on order from China so I'll know soon enough after they arrive. ?Has anyone else had an issue with this vari-cap diode?
|
John
I guess you can replace the varicap by a 1N4001 -1n4007.
Emerson PP6EW
Em sáb., 22 de jun. de 2024 às 20:34, A. John Hecht via <k6koi= [email protected]> escreveu:
I recently was given two FT101ZD's, one a "Parts rig" Mark I and the other a Mark II.? Both required work but both are now working.? I found I had to remove the voltage to PIN 2 of the VFO input connector to calm down the VFO in the Mark I. The VFO was moving like crazy and when it did settle down it still had an issue with warble.? Removing the voltage solved the issue but now of course the Clarifier function is no longer.? It appears that the variable-cap diode (D01) for the clarifier circuit is defective.? I have some of those diodes on order from China so I'll know soon enough after they arrive.? Has anyone else had an issue with this vari-cap diode??
|
I recently was given two FT101ZD's, one a "Parts rig" Mark I and the other a Mark II. ?Both required work but both are now working. ?I found I had to remove the voltage to PIN 2 of the VFO input connector to calm down the VFO in the Mark I. The VFO was moving like crazy and when it did settle down it still had an issue with warble. ?Removing the voltage solved the issue but now of course the Clarifier function is no longer. ?It appears that the variable-cap diode (D01) for the clarifier circuit is defective. ?I have some of those diodes on order from China so I'll know soon enough after they arrive. ?Has anyone else had an issue with this vari-cap diode??
|
Re: FT 101 EE Audio board
Em qui., 20 de jun. de 2024 às 22:15, James Fisher via <cadiscase= [email protected]> escreveu:
I have an FT 101 EE.
The Audio Board is? PB-1315.
I am replacing the electrolitic caps? and the Mylar caps.
Is there any change in cap values I should make that would improve the audio on transmit or receive ?
I think the FT101 could us a little more bass.?
Thanks?
James
|
I have an FT 101 EE.
The Audio Board is? PB-1315.
I am replacing the electrolitic caps? and the Mylar caps.
Is there any change in cap values I should make that would improve the audio on transmit or receive ?
I think the FT101 could us a little more bass.?
Thanks?
James
|
Re: Reconversion from 11M Local Oscillator alignment
Only the older ZD models have the display unit with the toggle switches. I can’t remember when the switched over to the later model.?
On Thu, Jun 20, 2024 at 5:40?AM Chuck, WS1L via <chandlerusm= [email protected]> wrote: Would that be the case for a 101ZD MkII?? I've never seen any toggle switches on the VFO although they could be inside the housing. ---------- Forwarded message --------- From: Bruce Collins via <kb0tj1=[email protected]>Date: Wed, Jun 19, 2024 at 12:40?PM Subject: Re: [Yaesu-FT-101] Reconversion from 11M Local Oscillator alignment To: < [email protected]> I’m pretty sure if it is showing MHz ?off, but is actually transmitting and receiving at the right frequency … it has nothing to do with the new 10m crystals.?
The older display units had toggle switches on them that mix signals to give you the right offset displays.?
Maybe better check that out in case it is adjustable.?
|
Re: Reconversion from 11M Local Oscillator alignment
Unplug the two wire harnesses from the display unit and clean the male pins. Plug them back in a few times to make sure all of them or connecting well. Retest.? If no good: As lame?as it sounds, I’d buy a new display unit on eBay, swap it out with the one in the radio now and if still no difference, put it back on eBay! You won’t get stuck with it, they sell fairly easily.?
On Thu, Jun 20, 2024 at 5:40?AM Chuck, WS1L via <chandlerusm= [email protected]> wrote: Would that be the case for a 101ZD MkII?? I've never seen any toggle switches on the VFO although they could be inside the housing. ---------- Forwarded message --------- From: Bruce Collins via <kb0tj1=[email protected]>Date: Wed, Jun 19, 2024 at 12:40?PM Subject: Re: [Yaesu-FT-101] Reconversion from 11M Local Oscillator alignment To: < [email protected]> I’m pretty sure if it is showing MHz ?off, but is actually transmitting and receiving at the right frequency … it has nothing to do with the new 10m crystals.?
The older display units had toggle switches on them that mix signals to give you the right offset displays.?
Maybe better check that out in case it is adjustable.?
|
Re: Reconversion from 11M Local Oscillator alignment
Thanks for that - is it any clue that this only happens when transmitting and the power is increased?? I was suspecting a supply voltage issue perhaps with the additional drain on TX.
Also, since it happens on 10m, 12m and 15m, I would suspect an issue with the actual display board or VFO board ?
I have had to remove these VFOs a few times over the years and remove the VFO cover, ?to just resolder every single joint on them to get the display to work right again.?
|
Reconversion from 11M Local Oscillator alignment
Would that be the case for a 101ZD MkII?? I've never seen any toggle switches on the VFO although they could be inside the housing. ---------- Forwarded message --------- From: Bruce Collins via <kb0tj1=[email protected]>Date: Wed, Jun 19, 2024 at 12:40?PM Subject: Re: [Yaesu-FT-101] Reconversion from 11M Local Oscillator alignment To: < [email protected]> I’m pretty sure if it is showing MHz ?off, but is actually transmitting and receiving at the right frequency … it has nothing to do with the new 10m crystals.?
The older display units had toggle switches on them that mix signals to give you the right offset displays.?
Maybe better check that out in case it is adjustable.?
|
Re: FT-101EE installing Processor board PB-1534
James
You can find instruction at
section 6-1.
73 Emerson PP6EW
Em seg., 17 de jun. de 2024 às 15:43, James Fisher via <cadiscase= [email protected]> escreveu:
I just got a FT-101EE.
It has the PB-1534 Processor board installed.
It works good except :
When in transmit and the meter is in the ALC position, there is no movement of the meter.
Yes I have turned the mic gain up CW.
I tried adjusting the ALC on PB-1184? but it makes no difference .? The needle is pined to the right.?
I read where the ALC adjustment is located on PB-1534.
I can move VR2 and it does move the needle to the left, but still no 'uptick' when I modulate USB
Are there issues with installing the PB-1534 in a FT-101 EE? ??
Are there any instructions for installing? the PB-1534 in an EE ?
Thanks
James
|
Re: Reconversion from 11M Local Oscillator alignment
Also, since it happens on 10m, 12m and 15m, I would suspect an issue with the actual display board or VFO board ?
I have had to remove these VFOs a few times over the years and remove the VFO cover, ?to just resolder every single joint on them to get the display to work right again.?
|
Re: Reconversion from 11M Local Oscillator alignment
I’m pretty sure if it is showing MHz ?off, but is actually transmitting and receiving at the right frequency … it has nothing to do with the new 10m crystals.?
The older display units had toggle switches on them that mix signals to give you the right offset displays.?
Maybe better check that out in case it is adjustable.?
|
Reconversion from 11M Local Oscillator alignment
I have a FT-101ZD late Mk2 that had been converted to 11M years ago.? I recently got around to locating the correct crystals and have aligned the TX mixer, driver and RX front end stages per the service manual.? I get good output on all bands and good sensitivity as well.??
However, when transmitting on 15, 12 and 10 meters with more than a few watts of output, the VFO shows an incorrect frequency - several MHz low, not always the same.? Checking the output on another radio shows the transmitted signal is where it should be, so it's the VFO that is displaying the wrong frequency.??
I suspect I need to align the premix local board where the proper crystals have been installed, but the service manual is a bit brief in it's description of the process.??
Does anyone have a "cheat sheet" for this, or perhaps someone has done a video?? I have an oscilloscope, and could whip up a simple RF probe if needed.??
|
Re: FoxTango laminated sheet
If you are on Facebook, go to the files section of the group called: Keeping The Yaesu FT-101 Alive! ?
|
The Fox Tango Club used to have a laminated sheet with Top/Bottom of a FT 101 with alignment points indicated.
Does anyone have a digital copy of this document they could send me ?
Is it still available to buy ?
Thanks
James? NQ7L? ? ? cadiscase@...
|
FT-101EE installing Processor board PB-1534
I just got a FT-101EE.
It has the PB-1534 Processor board installed.
It works good except :
When in transmit and the meter is in the ALC position, there is no movement of the meter.
Yes I have turned the mic gain up CW.
I tried adjusting the ALC on PB-1184? but it makes no difference . ?The needle is pined to the right.?
I read where the ALC adjustment is located on PB-1534.
I can move VR2 and it does move the needle to the left, but still no 'uptick' when I modulate USB
Are there issues with installing the PB-1534 in a FT-101 EE? ??
Are there any instructions for installing? the PB-1534 in an EE ?
Thanks
James
|
Re: Electrolytics - FT-101B
Sorry- my reply never went through.? Yes, I have the cap on the audio choke.
|
Jim Shorney
Bruce Collins
Chuck, WS1L
Tom ai4th