Re: Active Car Radio Aerials
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Hi some pictures
The active aerial from the Citreon ,only has a 50 ohm cable.
the amplifier inside the aerial
and the in line amplifier I bought on line.
I had to make a filter to power this up.
The intention is to fit this amplfier inside the aerial unit
I have seen an aerial that looks exactelty the same with two leads on line
It would mean running a cable from the radio...
barry wilkins
Senior Member
Last Activity: 03-04-2023, 11:21 AM
Joined: 08-31-2009
Location: Maidstone Kent
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Re: Active Car Radio Aerials
The cable to the radio is just 50ohm coax .
Same as sattelite ,DC voltage on the inner wire to the amp.
RF goes back to the radio.
So you use a biased tee filter to power the amp.
When the weather improves going to remove the aerial again {it aint easy to remove}
Found an intersting circuit that use an IC MAX circuit .
So might try that.
BarryLeave a comment:
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Re: Active Car Radio Aerials
Checked the radio out of the car ,sure it ok
Bought an inline amplfier ,had to make a biased tee to get the 12 volts from the radio lead.
But its not that good.
One of the problems the freq. keeps changing as you drive .Dont think the transmiiters are very good where I live.
BarryLeave a comment:
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Active Car Radio Aerials
Does any body have circuits on the amplifiers used in these car radio aerials.
The unit in my Citreon is low gain,think water got into it.
I have removed it and dried it out,but it did not make it work any better.
Now the better weather is on its way . I intend to remove it and look at it again.
Its a pig to remove bceuase of the roof lining ,so I want to fix it this time.
Barry -
Re: Battery Charging Peugot Boxer
It was a poor conection.
Yes the van has a Tyco isolator relay that disconnects most of the electronics to stop the battery discharging.
I understand this is a bistable relay
My old van was a Ducato ,I fitted a 100A switch in the lead from the battery to the fuse box to stop thuis from happening.
BarryLeave a comment:
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Re: Battery Charging Peugot Boxer
Got to the bottom of it.
A fuse in the power feed from the battery,no mention of it anywhere.
Barry...Leave a comment:
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Re: Aneng dt 9205a dvm
It might be the new chip which has 44 pins
R34 is connected to pin 39 (100K) reducing by padding this with 10M has brought up the reading .Its slightly high now .
One of those tiny pots would be nice ,but have never found them anywhere.
I have got some SM 10M resistors left over from a scope repair ,so I will fit one of them.
BarryLeave a comment:
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Re: Aneng dt 9205a dvm
Hi I did find some info on line ,which I did not think was correct . It showed a circuit with 7106 IC.
I wiil take a look next week.
BarryLeave a comment:
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Re: Aneng dt 9205a dvm
dont know what happened with the picture...Leave a comment:
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Re: Aneng dt 9205a dvm
Hi cant tell what the chip is attached a picture .
I know this was quite cheap ,bought it from Amazon because I had blown workshop one on some Ferrus power supplies, in fact its not bad just a bit low on all readings,when I compare it with my best meter which is accurate.
Just would like to increase the counts which will make it bit better.
If you see my other post ,I found a resistor O/C on the Maxcom ,so got lots of meters now 8 or 9 .
3 scopes.
BarryLeave a comment:
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Battery Charging Peugot Boxer
I am having a problem with the starter battery in my motor caravan, the makers info is very poor so I am struggling a bit with this.
As it is Euro 6 I think the charging is done by the ECU,not the spilt charge system with relays.
I managed to start the engine after a boost and the voltage rose to about 14 volts ,but now it is about 11.5 volts.
It is not charging by the EHU where the 12volt power supply is.
It is quite complex .
Starter battery
Liesure battery
Solar panel
BCA module with relays fuses and the power supply
The fuse in... -
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Re: DVM circuits
I could see there was something wrong around the TL 062 opamp ,so I removed it and replaced it with an 072 ,replaced the diodes and capcitors at the same time. A bit more investigation found R 36 was O/C.
Barry...Leave a comment:
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Re: DVM circuits
Hi thanks to all of you for the info ,I will look at it in a few days .
Not too bothered about fixing it as I have quite a few other meters
1 I keep my car 1 in my tool box 1 in my caravan, 3 in my little workshop , a TEK scope and a Hantek scopemeter.
regards
BarryLeave a comment:
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Re: DVM circuits
Hi attached some pictures cant see any makers name on it .Fixed the noise problem by cleaning the switch ,just seems a problem trying to measures diodes ,very low voltage applied to the device .
There are two op amps ,dual and a quad .
Could it be a problem with the LM324 ?
Bought a new one from Amazon that had 1000 V on it ,was rubbish didnt have any sockets fitted for the transistors, so it returned it.
Got a different one which is better.
Barry...Leave a comment:
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DVM circuits
Unforunately I damaged one of my DVM,s when working on some power supplies
measuring some high voltages ,because there was some rf on the dc I was measuring.
It still works but is noisey and it will not measure diodes, I would like to fix it if possible.
Does any one have any circuits for DVM,s
thanks
Barry Wilkins -
Re: SOVOS Flip down TV SVKTV156A
Hi yes cleaned up the mess.
Perhaps when the board was made they did not have the proper surface mounted capacitors.
Attached some more pictures .
Got the 12 volts and 5 volts working .
Just need the new caps to come from ebay.
Barry...Leave a comment:
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Re: Any experiences with this ESR meter circuit?
I made one some years ago,the only problem was a bit of drift .
I fitted a small bulb in the oscillator ,that cirtainly made a big difference.
Pinched the idea from HP
Barry WilkinsLeave a comment:
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Re: 4017 counter reset problem
Thinking about it I decided to use two transistors in a darlington configuration .seems to work OK .
Next step is to try it out.Leave a comment:
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Re: SOVOS Flip down TV SVKTV156A
I dont know i,t is right bodge took a lot of getting off.
I spoke to the owner and she said it had never been repaired before ?
As I said before the caps are far too large ,jammed in and glued down ,if what I was told is correct it was done by the manufacturer.
BarryLeave a comment:
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