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http://www.iw2nmx.it/Yaesu/FT-301/FT-301%20Instruction%20and%20Service%20Manual.pdf

I read where Yaesu had a workaround for the TA7089M using the DIP version and that would work for me too. Also a working PB-1436B IF board would work The radio powers up but the VFO doesn't work and appears there is no regulated 6v to it supplied by the above IC Any Leads appreciated. I came into possession of a 301D with the power supply, VFO, and the scope. The radio powers up but the VFO doesn't work and appears there is no regulated 6v to it supplied by the above IC Thanks! Marty KL7AM

Test

The following files and folders have been uploaded to the Files area of the [email protected] group. /ft_301-s(jp).pdf By: Jim <james_buttons@...> Description: Japanese version of FT-301/S. Even though in Japanese, the schematics are good and are for very early (s/n) of the 301 (non D) & S versions. Allso contain schematics of front panel analog LED indicator

pb1433 rf board output of Q104 board pin 14 going into t3 is a beautiful sine wave. output of t3 going to board input pin 15 is trashy noisy. I sprayed the band selector wafers with deoxit and gave it a good workout but it is still the same. dirty signal. what can i do to fix this? Is the noise caused by the resistors? The board produces no tx output. SN7400 output is good, Q106 swapped out with a good one, rf no output, Q105 replaced with a good one, no output. removed Q105 and q106. Placed good rf board and bad one side by side and ohmed it out compairing readings and are reading identical.I am at a loss, it should work but does not. !!. anyone with RF board experience advice would be greatly appreciated. Thanks, Robert KH2BR

Concerning the display chips and the FT301D. It was perhaps two years after obtaining my 301D in 1977 that my first display chips failed. I ordered some new replacements and corrected the problem. I found that if the rig was used day after day the display chips lasted several years. I noticed when the rig was shut down for an extended period of several months to several years there were always segments out when I repowered the rig. Then I began to notice that even a few of the brand new chips had defective segments. This got me wondering; could "whiskering" which was a fairly common problem of the 1970's area be the culprit? Some materials in chip, pcb, and discrete component production would grow little bitty whiskers that would short and take out delicate electronics. NASA and others lost a number of satellites due to whiskering problems in space. The US military loss due to this is still classified. The little whiskers can be inside components, outside components, around pcb traces and so forth. Why else would brand new TIL chips that hadn't been in circuit nor had they suffered any heat mysteriously show up with the same kind of segment problems as the ones operating for several years installed in the rig? Fortunately I have enough spares on hand that I can sort through them to get enough good ones operating correctly. I picked up a stock of them back in the day "just in case." :-) This is open for discussion but I think the problem was a manufacturing defect perhaps the well known whiskering problem and not related to burn out and so forth. Parts don't burn out that are sitting in storage, but whiskers do grow while in storage and sitting on the shelf. https://nepp.nasa.gov/whisker/reference/tech_papers/2006-Leidecker-Tin-Whisker-Failures.pdf

Anyone have spare FT301 parts?

I need help in finding the 6 volt regulated power source for the VFO. Been thru the schematic many times and cant find it. Thanks, Robert

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

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.

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.

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. https://hamwaves.com/decibel/en/ (which in turn, has references) http://www.iz2zqg.radio/en/thoughts-regarding-the-s-meterS9 + 20db = -43 dbm (meter reads 10 db low) http://lists.contesting.com/_yaesu/1997-11/msg00056.html ( 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

A new poll has been created: 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! 1. bIMG_0720(b-b-b).JPG 2. bIMG_0725(b-g-g).JPG 3. bIMG_0726(b-r-r).JPG 4. bIMG_0729(b-g-r).JPG 5. gIMG_0722(g-b-b).JPG 6. gIMG_0723(g-g-g).JPG 7. gIMG_0727(g-r-r).JPG 8. gIMG_0730(g-b-r).JPG 9. rIMG_0717(r-b-b).JPG 10. rIMG_0724(r-g-g).JPG 11. rIMG_0728(r-r-r).JPG Click Here To Vote Do not reply to this message to vote in the poll. You can vote in polls only through the group's website.

Jim <james_buttons@...> added the album 301 band pass filter alignment results: various pictures of results obtained for a 301 band pass filters for each band after completed alignment using a tracking generator/spectrum analyzer. The following photos have been uploaded to the 301 band pass filter alignment results album of the [email protected] group. 10a (balanced-with-11) bpf.png 11 (balanced-with-10a) bpf.png 15 bpf.png 10a (optimized) bpf.png 10 bcd bpf.png 20 bpf.png 40 bpf.png 160 bpf.png By: Jim <james_buttons@...>

Heading to electronic recycling soon. Free Charlotte, NC area Bo W4GHV wn4ghv at gmail