I found the microscopic part number and it is a PB1685
This board was in a FT301S. . any schematics for this one??
relay control is provided by a quad 2 input nand gate which drives a npn transistor and in turn switches another? npn transistor on which then activates the relay. I had to sub out the 2sc372 and 2sc735 with 2n2222a. it worked for a while then quit, so I am getting some where. Now, it hangs in tx. I will undo what I did and check the output of the gate.
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I have a vox board PB1438B and another one that does not have a PB number on it.
The B model has a sn72560 IC and mc14013 IC ..
The one with no part number has mc14024 and mc14011 Where can I find a schematic for this one with no part number.?
Attached is a photo of the board that has no part number. Its malfunction is that it will not key into transmit in cw. no break-in.
Robert
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It’s located on a small board behind the S meter. The Mic gain pot is facing up.
I was about to do the carrier point adjustments in the manual and looked for the mic gain adjustment and cant find it.
can anyone tell me where it is??
Thanks..
Robert
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I was about to do the carrier point adjustments in the manual and looked for the mic gain adjustment and cant find it.
can anyone tell me where it is??
Thanks..
Robert
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Re: New owner of a project 301D
Dear? Chris
Around two years ago, I start a restore of a FT-301d.
The FT-301 manual have enough information that can help you. The display is really a problem.? The best advice, if possible, is to buy a new from
About LSB and USB, the idea is to check both oscillators.
Another advice is replace tantalum capacitors c60 and c61 of 6u8 located at the chachi, before them burn out. The power voltage is 13V5, not 13V8 or 14V.
73 PP6EW Emerson
Em qua., 5 de out. de 2022 às 13:52, elkhider via <elkhider= [email protected]> escreveu:
Good morning all you smart people!
At a recent hamfest I bought a poorly 301 for a whole $10. The tag said "bad display" but when I powered it up the display was working, except for 2 segments of the .0 section, no biggy there. What I found is that the display never changes in response to the VFO. It changes bands and displays the bottom of the band, but doesn't move from there. Also, on the lower bands like 80 and 40 I can get audio from USB, but not LSB, and above those frequncies I get sound on LSB but not USB. Contrary thing I guess. Since Yeasu apparently never released an actual service manual I'm wondering where to start with the beast??
I've pulled a few boards, gave the connections a deoxit treatment, it's amazingly clean inside for being such an old radio.
Cheers Chris N8FF
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New owner of a project 301D
Good morning all you smart people!
At a recent hamfest I bought a poorly 301 for a whole $10. The tag said "bad display" but when I powered it up the display was working, except for 2 segments of the .0 section, no biggy there. What I found is that the display never changes in response to the VFO. It changes bands and displays the bottom of the band, but doesn't move from there. Also, on the lower bands like 80 and 40 I can get audio from USB, but not LSB, and above those frequncies I get sound on LSB but not USB. Contrary thing I guess. Since Yeasu apparently never released an actual service manual I'm wondering where to start with the beast??
I've pulled a few boards, gave the connections a deoxit treatment, it's amazingly clean inside for being such an old radio.
Cheers Chris N8FF
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Re: FT-301 alignment: clarifier zero setting
I have not noticed a problem with this…..I did a complete realignment according to the handbook and have not had a calibration problem since, so I can’t help. D.
The 301 I am working on needed this badly. The clarifier knob was a full mark to the left in order for the receive audio to be the same with the clarifier on/off.
The instructions are straightforward, the only thing that surprised me was that when moving the adjustment pot, it doesn't change the frequency of the clarifier to the radio frequency, it shifts the radio frequency to the clarifier setting - weird, but it works.
I also noticed that after this adjustment, it seemed like the linearity of the frequency readout was improved as I tuned across the 80 m band from 3.5 - 4.0 Mhz. I can't 100% confirm this, but now when I tune and check every 25 KHz against the marker, it just needs a very minor tweak across the entire range. I don't think it was like this previous. I would be curious if anyone else doing this adjustment has seen anything similar.
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FT-301 alignment: clarifier zero setting
The 301 I am working on needed this badly. The clarifier knob was a full mark to the left in order for the receive audio to be the same with the clarifier on/off.
The instructions are straightforward, the only thing that surprised me was that when moving the adjustment pot, it doesn't change the frequency of the clarifier to the radio frequency, it shifts the radio frequency to the clarifier setting - weird, but it works.
I also noticed that after this adjustment, it seemed like the linearity of the frequency readout was improved as I tuned across the 80 m band from 3.5 - 4.0 Mhz. I can't 100% confirm this, but now when I tune and check every 25 KHz against the marker, it just needs a very minor tweak across the entire range. I don't think it was like this previous. I would be curious if anyone else doing this adjustment has seen anything similar.
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FT-301 alignment: Marker Generator Frequency
WWV (5 Mhz, LSB) receive was off frequency on the rig I am working on.
Instructions are straight forward, no special equipment, just an antenna and able to receive WWV 5.0 Mhz (likely easier after dark - at least in North America).
An alternative would be to input using a signal generator, but would need to offset by 1.5 KHz to zerobeat since this this receiver is set to LSB for receive. It helps if listening during the minutes when WWV is broadcasting a tone and have a 2nd (calibrated) receiver to match the tones by ear.
Also adjusted (zero beat) the marker at the same time, as stated in the manual.
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Re: FT-301 No Tx Output - Solved!
Hello there just joined the group .
i have ?recently bought one of these 301s been using for receive which is great ! On tx there seems to be no output but the needle slams over like u never seen a needle move before ! ! Could this be the same issue .
it will do this in any mode . Key the mic or vox switch and the needle just slams over . Any ideas or help would be great thanks .
neil ?
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FT-301 alignment: s-meter
Looking through the 301 manual's alignment instructions for the s-meter, I immediately had a question about the signal generator levels all refering to "db". db is a relative measurement and levels need a reference. A reference to what was the question in my mind. So it was a bit confusing. After a little research, it became clear that the levels in the manual are dbuV (decibels per microvolt). The issue with using dbuV is that it doesn't necessarily specify into what impedence. Most modern equipment has settled on using dbmW (decibels per milliwatt into 50 ohm resistive load). With the help of information from the following sources, I was able to equate the levels in the manual to levels that my sig gen could use.
(which in turn, has references)
( a really old reference, but not old, considering the era that the 301 was designed in)
So, the next issue is that yaesu meters (from this era), in general, seem to be "tight" on the s-units. This includes my FT-101E. This is somewhat understandable since at the time, the IARU hadn't yet adopted the -73dbm level for S9 that Collins Corp. had been using for years (per references above). I am not going to discuss the 3db or 6db per s-unit debate. For this 301, I decided to see how close I could get it to the IARU standards.
I ultimately ended up with being mostly successful:
S4 = -103 dbm
S7.5 = -83 dbm (This was just a check because I could put in 20db of attenuation quickly) S8 should be -79, S7 should be -85, so close enough...
S9 = -73 dbm (the "gold" standard number)
S9 + 10db = -58 dbm (meter reads 5 db low)
S9 + 20db = -43 dbm (meter reads 10 db low)
Above S9 + 10db, the meter reads low, but I'm okay with that because any signal above S9+10db is "59" anyways... The weak signals are the ones that I would like to give accurate reports for.
Because of the circuitry design, the meter likely can't be fully calibrated to IARU without changes to the circuit (I am not that ambitious to do this at this time), I ultimately toggled between S4 & S9, checking at S1 and S9+5 and once that was done, I checked at the higher levels +10, +20, +40, +60 and live with the lower readings. One additional note, in the yaesu cal, they use 80 dbuV for S9+60 (full scale), however 80 dbuV actually is ~S9+45 in the IARU world.
We'll see, if I don't like it, I can always change it.
The rig is on right now, listening to 40m nets at the moment.. Sounds good and the meter "is a movin"
(next up, the clarifer center on/off is out by quite a bit, the alignment seems simple enough)
That's all for now.
-Jim
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Re: FT-301 alignment: Band pass filter adjustment results
Forgot one attachment, shows display quality.
On 9/5/2022 6:33 AM, Randy W7CPA wrote:
toggle quoted message
Show quoted text
The Elcon site only has some English.
I had to copy-past-translate a bit.
The owner speaks perfect English in emails.
I worked with him to build a universal VFO Stab to go with the
301 specific model.
I deployed it in my SB-104A.
He lives in a tiny Swiss city in the Alps.
Superb engineering, rock solid VFO now.
The display system is likewise superb.
It comes with a little Phillips remote control to change setting
with.
Way cool.
100% AM MOD requires tat you set the carrier level on the AM
board down to 20-30 watts the leave headroom.
I use a D-104 with? picky AM group out here.
The Elcon displays are clear and sharp.
My camera is making them look fuzzy.
Cheers,
Randy
W7CPA
On 9/5/2022 5:40 AM, james_buttons
via groups.io wrote:
Thanks Randy.
I'm probably going to go trhough the entire alignment. I
purchased the rig as the 3rd owner. When I talked with the
previous owner, he had not done any work on the rig, but there
are notes written in the (original) manual that leads me to
believe that someone else (the original owner?) had attempted
performing "adjustments". Not knowing that state of the rig
because of this, I will likely attempt a full alignment. I will
end up doing this piecemeal over the coming weeks/months as I
still work full time and don't have large blocks of time.
This approach works for me, as I use the rig in between and see
if there are any improvements. - It's like getting a new rig
after each alignment :) ....
FB on the ELCON - everytime I've gone to their site, I can't get
the site in English to be able to order. With the latest world
events, I'm not even sure I could get one now. I do have a 301D
that will be next on my list after I finish up with this 301 and
this "D" does have missing LED segments, so I will have to do
something..
Cool in the AM. I read somewhere once that this rig is good on
AM, I will be checking it out. A good candidate for a D-104
perhaps....
I just finished the s-meter alignment (in a new thread).
Take care.
-Jim (NO2P)
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Re: FT-301 alignment: Band pass filter adjustment results
The Elcon site only has some English.
I had to copy-past-translate a bit.
The owner speaks perfect English in emails.
I worked with him to build a universal VFO Stab to go with the 301
specific model.
I deployed it in my SB-104A.
He lives in a tiny Swiss city in the Alps.
Superb engineering, rock solid VFO now.
The display system is likewise superb.
It comes with a little Phillips remote control to change setting
with.
Way cool.
100% AM MOD requires tat you set the carrier level on the AM board
down to 20-30 watts the leave headroom.
I use a D-104 with? picky AM group out here.
The Elcon displays are clear and sharp.
My camera is making them look fuzzy.
Cheers,
Randy
W7CPA
On 9/5/2022 5:40 AM, james_buttons via
groups.io wrote:
toggle quoted message
Show quoted text
Thanks Randy.
I'm probably going to go trhough the entire alignment. I purchased
the rig as the 3rd owner. When I talked with the previous owner,
he had not done any work on the rig, but there are notes written
in the (original) manual that leads me to believe that someone
else (the original owner?) had attempted performing "adjustments".
Not knowing that state of the rig because of this, I will likely
attempt a full alignment. I will end up doing this piecemeal over
the coming weeks/months as I still work full time and don't have
large blocks of time.
This approach works for me, as I use the rig in between and see if
there are any improvements. - It's like getting a new rig after
each alignment :) ....
FB on the ELCON - everytime I've gone to their site, I can't get
the site in English to be able to order. With the latest world
events, I'm not even sure I could get one now. I do have a 301D
that will be next on my list after I finish up with this 301 and
this "D" does have missing LED segments, so I will have to do
something..
Cool in the AM. I read somewhere once that this rig is good on AM,
I will be checking it out. A good candidate for a D-104
perhaps....
I just finished the s-meter alignment (in a new thread).
Take care.
-Jim (NO2P)
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Re: FT-301 alignment: Band pass filter adjustment results
Hi Michael,
I've worked with many technical writers in my career and I have a lot of respect for them because it's extremely difficult to write technical guides not knowing the experience of the end-user or what equipment they are using. It's difficult to post instructions, because of this. Not too mention any liability if someone happens to blow up their rig or (more likely) what can be very expensive test equipment.? One mistake can put 100w into equipment designed for micro-volts and puff there goes $1000's.. Many years ago, I blew up an HP-435b power meter (forgot to put the 60db attenuator in front of it). I learned a very valuable lesson early in my professional life.. You typically only make this mistake once.... One I will never forget..
Basic equipment setups can be found on the web. The yaesu guide is "okay" considering when it was written (in the 70's). I have more to say on this in a new thread for the s-meter alignment (coming soon).
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Re: FT-301 alignment: Band pass filter adjustment results
Thanks Randy.
I'm probably going to go trhough the entire alignment. I purchased the rig as the 3rd owner. When I talked with the previous owner, he had not done any work on the rig, but there are notes written in the (original) manual that leads me to believe that someone else (the original owner?) had attempted performing "adjustments". Not knowing that state of the rig because of this, I will likely attempt a full alignment. I will end up doing this piecemeal over the coming weeks/months as I still work full time and don't have large blocks of time.
This approach works for me, as I use the rig in between and see if there are any improvements. - It's like getting a new rig after each alignment :) ....
FB on the ELCON - everytime I've gone to their site, I can't get the site in English to be able to order. With the latest world events, I'm not even sure I could get one now. I do have a 301D that will be next on my list after I finish up with this 301 and this "D" does have missing LED segments, so I will have to do something..
Cool in the AM. I read somewhere once that this rig is good on AM, I will be checking it out. A good candidate for a D-104 perhaps....
I just finished the s-meter alignment (in a new thread).
Take care.
-Jim (NO2P)
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Re: FT-301 alignment: Band pass filter adjustment results
Nice work sir, I didn't touch mine, Manual is so poor and they were close enough.
I replaced display with the excellent ELCON product.
I also added the ELCON frequency stablizer.
Radio is playing extremely well.
AM is steller with good mic.
Randy
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An FT-301 that I'm working on has 1 of the 3 main display bulbs burned out. Instead of replacing it with a boring :) incandescent (assuming that I could even find one), I've always been curious what it would look like to use colored LEDs and what better than to use a couple (3) RGB LEDs and see what the various color combinations would look like. I have a certain preferences, but I will hold off disclosing them until after the poll results come in. I've uploaded an album (with the same name) that contains a series of pictures. Each answer below corresponds to a picture with three letters in it's name. example gIMG_0730(g-b-r).JPG The letters in parenthesis correspond to the LED color for the "meter"-"left display"-"right display". In this example, the picture "gXXXX(g-b-r).JPG" shows the meter with green, the left display with blue and the right display with red. (PS - certain combinations just didn't work aesthetically, so they aren't here) So vote for the color combinations that you like the most. Multiple choices are allowed!
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Re: FT-301 alignment: Band pass filter adjustment results
Hi Jim,
Thanks for uploading these pictures. Could you send how you connected the equipment to be able to get those results? This might help others to do the same. The Yaesu manual is not good with details. It would be great if we could have a library of other adjustments that the manual/service does not show but are important as well.
Michael
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Michael K.