Yaesu FT-890 ALC reading - UK Vintage Radio Repair and Restoration Discussion Forum

GSBX1220 · 22nd Oct 2018, 9:55 pm

Hi folks

With regards to my other thread where I mulled over getting an HF set, I now have one.

It's a Yaesu FT-890 fitted with the narrow CW and improved SSB filters. It also has the internal ATU which seems to tune the 1/2 wave dipole I made for 10m on all bands.

The rig is immaculate without a doubt.

Had a play with it between Saturday and yesterday and made some quick QSOs on 40 and 20. Furthest worked was Czech Republic.

One thing I noticed was how the ALC meter reads. However far I adjust the mic gain I cannot get it to kick past the upper part of the thick blue ALC line. Not that you want it there, but it won't go past it.

Also if I turn the rf power down to around 50w, I can get the ALC meter to deflect slightly higher than on full power.

On full power, the PO meter can peak at 125w on speech peaks. So seems a good healthy PA.

Maybe a silly question, but I presume this is normal for ALC. this rig is high tech for me and my first real foray into HF!

Cheers.

Steve G4WCS · 23rd Oct 2018, 8:43 am

Tidy looking radio, Looks like theyve recycled the FT-757 castings and put more functionality in.

Ive linked to the service and operating manuals. p18 of the operating manual describes using the ALC to set mic gain control, I always set is so its just starting to flicker onto the ALC on voice peaks, then use the RF power to control to set the desired RF power output. overdriving the mic gain into heavy ALC leads to distortion, and extraneous noises being transmitted

http://www.radiomanual.info/schemi/Y...T-890_serv.pdf

http://www.radiomanual.info/schemi/Y...T-890_user.pdf

GSBX1220 · 24th Oct 2018, 12:56 pm

Hi

Thanks for the links. Radio came in original box with DC lead, mic and manual. All like brand new!

It is indeed a nice compact rig with lots of features. One feature not mentioned in the manual is that you can change the tone of both RX and TX audio. No idea why this is not in the manual.

I was unsure about the ALC scale as the manual said to make sure the needle does not deflect past the upper part if the thick blue ALC line.

No matter how much much gain I give it, I cannot manage much past 3/4 up the scale, so I presume the radio is quite good at limiting by itself.

HF in the evening is a challenge due to the noise levels. SMPSU units have a lot to answer for!

22nd Oct 2018, 9:55 pm	#1
GSBX1220 Pentode Join Date: Jun 2018 Location: Glasgow, Scotland,UK. Posts: 127	Yaesu FT-890 ALC reading Hi folks With regards to my other thread where I mulled over getting an HF set, I now have one. It's a Yaesu FT-890 fitted with the narrow CW and improved SSB filters. It also has the internal ATU which seems to tune the 1/2 wave dipole I made for 10m on all bands. The rig is immaculate without a doubt. Had a play with it between Saturday and yesterday and made some quick QSOs on 40 and 20. Furthest worked was Czech Republic. One thing I noticed was how the ALC meter reads. However far I adjust the mic gain I cannot get it to kick past the upper part of the thick blue ALC line. Not that you want it there, but it won't go past it. Also if I turn the rf power down to around 50w, I can get the ALC meter to deflect slightly higher than on full power. On full power, the PO meter can peak at 125w on speech peaks. So seems a good healthy PA. Maybe a silly question, but I presume this is normal for ALC. this rig is high tech for me and my first real foray into HF! Cheers. __________________ Richard

23rd Oct 2018, 8:43 am	#2
Steve G4WCS Heptode Join Date: Sep 2004 Location: Preston, Lancashire, UK. Posts: 632	Re: Yaesu FT-890 ALC reading Tidy looking radio, Looks like theyve recycled the FT-757 castings and put more functionality in. Ive linked to the service and operating manuals. p18 of the operating manual describes using the ALC to set mic gain control, I always set is so its just starting to flicker onto the ALC on voice peaks, then use the RF power to control to set the desired RF power output. overdriving the mic gain into heavy ALC leads to distortion, and extraneous noises being transmitted http://www.radiomanual.info/schemi/Y...T-890_serv.pdf http://www.radiomanual.info/schemi/Y...T-890_user.pdf

24th Oct 2018, 12:56 pm	#3
GSBX1220 Pentode Join Date: Jun 2018 Location: Glasgow, Scotland,UK. Posts: 127	Re: Yaesu FT-890 ALC reading Hi Thanks for the links. Radio came in original box with DC lead, mic and manual. All like brand new! It is indeed a nice compact rig with lots of features. One feature not mentioned in the manual is that you can change the tone of both RX and TX audio. No idea why this is not in the manual. I was unsure about the ALC scale as the manual said to make sure the needle does not deflect past the upper part if the thick blue ALC line. No matter how much much gain I give it, I cannot manage much past 3/4 up the scale, so I presume the radio is quite good at limiting by itself. HF in the evening is a challenge due to the noise levels. SMPSU units have a lot to answer for! __________________ Richard