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Hello,

I just finish making one good FT-301D from 2 junkers and learned a lot about the beast. See my photos. I strongly recommend you install the Elcon VFO stabilizer in yours. They drift 400-500 annoying Hz. Does yours have the optional Speech Processor? The biggest problem is the aging SSB filters. INRAD has expensive replacements but for not much longer. The crystals in these old filter change a little bit over time.

Cheers,

Randy

Hi Nick.? It is hoped that this is becoming and will be the place for FT-301 owners so welcome.? You are probably aware the D version has the digital dial and the standard version like yours has the analog dial.? Welcome to the group.

I am the new owner of an FT-301 (not the D version), and have been searching for a little hideaway among people that recognize such a boat anchor. They certainly are quirky radios, but I enjoy it very much.

Hopefully my lack of a digital display doesn't get me summarily dismissed.

73,
Nick (N1CCK)

I performed this mod, works well.
Use either two 150uH chokes in series like described in the text or one 300uh like I did.

Sounds great Randy!? It will look great.? Just one more note, the little wires to the little speaker in the rig can be delicate and break easily including the terminal on the speaker.? Hope you have lots of fun with this great rig.? It has one of the best receivers I have ever heard.? I'm also glad you worked your way through the alignment and the inconsistencies in the manual when doing so.? As you discovered it takes a bit of trial and error to figure it out.

Power Supply is next, neon indicator out, foam behind panel is rotting powder and repainting is required due to major abuse.?It works perfectly (13.5vdc) and the bigger speaker might sound a little better.

RB

Great going Randy and congratulations!

I created one nice unit out of 2 parts rigs. My quest was greatly extended by user manual errors and rabbit holes I wasted a lot of time on. I put some photos in Photos.

What I fixed/replaced:

o Display board replaced with Elcon EL-31 – see Files for details.

o Added Elcon excellent vfo stabilizer – see Files for details.

o Fixed low SSB output problem after way too many rabbit holes

User Manual in wrong on Page 19. IF Board Q403 does NOT amplify the DSB signal. It is a 0.3 unity gain impedance matching stage.

The schematic is wrong on the IF Board. Both Q403 and Q404 drain connects are shown connecting back to the gates – dumb. They should be connecting to D404 8 vdc, one horizontal line below.

Removed the SSB filter on the NB Card and wired NB Card back to factory configuration for no Speech Processor. Even when RF Processor off, the path is through 2 series connected SSB filters. If the filters are not identical, one can never get the carrier set point right, one SSB will have low power out. I tried some filters from spare boards to no avail. I am going to use the MFJ-653 anyways so I don’t need screaming weeeeeemy DX audio anyway.

o I re-calibrated all except band pass, none were very far off so goodness.

o Cabinet – came out well.

I painted the trim ring with gloss black appliance enamel.

I over-sprayed cabinet with semi-gloss black enamel.

o I cleaned all switch wafers with DeOxit

o I cleaned all pots with DeOxit Fader Lube

o Power out can go up beyond 160 watts but I adjusted the pot on the NB card not to exceed 110 to be safe.
o Added 12vdc white LED to meter side light, looks nice, photo is exaggerated bright.
o Replaced burned out bulbs in the center indicator for VFO, Clarifier, EXT. This is a horrible job given Yeasu epoxied the the holder into the back of the face plate - stupid overkill.

?

Summary

CONS

o Not many flaws, this is an excellent design and after mods is even mo better.

o Little plastic cover push fasteners are unobtanium.

PROS

o Internal speaker is the best I’ve ever heard, no need for external speaker.

o Carrier suppress (after fader lube applied to pot) is best I’ve ever seen on older radios. -70db

o AM is superb both XMT and REC with optional AM Board. My REA monitor shows 120% positive with a 30 watt carrier and perfect wave forms.

o Semi-breakin CW and VOX works well.

o SSB quality is excellent as long as carrier set point is 6 db down. With 50 watts output at 1,000Hz mic input, 2mV, 300 Hz mic in must be 6db down at 12.5 watts out. Set this ONLY after a long warm up because there is minor drift of the SSB oscillators on the AF Board.

o Small package and styled beautifully.

o Someone installed a CB crystal (41.5 MHz) in the AUX position and it works.

o NB works well and 60Hz pulse crapolla.

o REC sensitivity and selectivity are excellent – comparing to my FLEX 5000 and KWM-2A

I just noticed, only TWO of us FT-301 nutters.
Too bad.

Yeah, what I am doing. I have found so many manual errors....

Page 31 (c) wants to monitor pin 11 on the "Filter Unit". There is no pin 11 on the filter unit and further, the filter unit is a stage behind the NB board and makes no sense for these adjustments.

Anyone have any knowledge here?

I have never been a moderator before and the settings are many.? Please try it again and hopefully it will work.? Let me know if not.? Bye for now.

I have a better quality PDF without the "SHOP" magic marker scribble but I can't upload.

I am blocked uploading the Elcon display replacement doc.
What gives?

I had to learn a lot about the IF Board on the road to final diagnosing my SSB low power out problem.
IF Board Q403 description lies. It does not amplify the DSB signal coming from the AF Board.
The gain of the weird JFET circuit Q403 is about .3 unity gain.
The circuit is a buffer/impedance matching circuit.
Also, the IF Board schematic has 2 major errors.

Is there an Yeasu internal doc that shows ANY levels on board pins?
Yeasu seem to be devoid of any levels in their docs.

I need to ask Roland about his instructions for this mod.
It says to put 2 150uh chokes in series but his Figure 3 only shows one choke.
Hopefully he installed a 300uh choke before he took the pic
I will post what he says.

Randy sounds like you are getting a great handle on putting another FT-301D on the air.? Congratulations.

The Elcon modification to the FT-301D filter board is now posted in the Files section.? Elcon claims the skirts of the SSB filter are improved through a better, more precise termination of the filter.

Hello,

I have begun an attempt to make one good one out of two parts rigs. So far so good. The big problem so far is a bad SSB filter, waiting on delivery of a parts rig with 2 filter boards. Hopefully one filter will play. This is a very interesting little transceiver.?

Cheers all,

Randy