Thanks all for your inputs.
I did order the caps mentioned.
Dave, I remember as young ham, abt 17 - 18 yo, charging 2 -3 kv DC
electrolytic caps then short them out with a screwdriver.
It was fun to see and hear the loud bang. Its amazing what we as kids...
On Wed, Jan 31, 2024, 10:22 PM Leeson <leeson@earthlink.net> wrote:
> A safety point: A good motor cap can hold the instantaneous value of the
> alternating voltage at the moment of disconnect. It's good to short it
> before touching the terminals. I use a jumper, and the zap and arc at
> times is quite surprising.
>
> Dave, W6NL/HC8L
>
> On 1/31/24 1:31 AM, maflukey@gmail.com wrote:
> > Starting caps come in value ranges. My experience is that slightly higher
> > values generally pose no issue, whereas too small may not be enough to
> get
> > the motor started under load. Try it to confirm. If motor stalls on
> > startup, stop and go to a larger cap.
> >
> > Hope this helps and good luck on your project.
> >
> > 73
> > Matt
> > KM5VI
> >
> >
> >
> > -----Original Message-----
> > From: TowerTalk <towertalk-bounces@contesting.com> On Behalf Of Joe
> Subich,
> > W4TV
> > Sent: Tuesday, January 30, 2024 7:52 PM
> > To: Raymond Benny <rayn6vr@gmail.com>; [TowerTalk]
> > <towertalk@contesting.com>
> > Subject: Re: [TowerTalk] UST Tower MA770 Starting Motor Capacitor
> >
> >
> >
> > > How rigid is the 375MFD value?
> >
> > Not that rigid ...
> >
> >> I have found on eBay a cap, 378-454 uF MFD at 250VAC. Would this meet
> >> the starting cap value?
> > Easily.
> >
> > 73,
> >
> > ... Joe, W4TV
> >
> > On 1/30/2024 8:39 PM, Raymond Benny wrote:
> >> I've had a MA770 tubular tower in the air for the last 15 years. I
> >> got it second hand 20 years ago. It's probably 40 years old. I need to
> >> replace the raising motor starting cap.I have the old cap in my hand
> >> and all I can read is 375 MFD. The motor operates on 120VAC. The motor
> >> name/data plate has been painted over, so I cannot read anything about
> >> it
> >>
> >> I have several questions:
> >> Does anyone have the make, model number or manufacturer info for MA770
> >> motor? And the info on the starting cap?
> >>
> >> How rigid is the 375MFD value? I have found on eBay a cap, 378-454 uF
> >> MFD at 250VAC. Would this meet the starting cap value? I know I don't
> >> need 240 VAC rated, but one rating should not be a problem. The
> >> measurements given for the cap will fit into the external cap holder.
> >>
> >> Thanks,
> >> Ray,
> >> N6VR/W7YA
> >>
> >
> >
> >
> > _______________________________________________
> >
> >
> >
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> >
> >
> > _______________________________________________
> >
> >
> >
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> >
>
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>
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