Hammarlund HQ 180-A Front end RF alignment, K7PP

[@gbowne1]

Yeah that does help, And, that's what I was thinking too. But all the information I seen on it wasn't that specific. I had a similar radio I'm not sure which model as it was quite a long while ago.

[@dogtagsvette]

That's a great question. They kinda look the same. The 170 is Amateur Radio Bands, only. The 180 series is General Coverage. All frequencies between Broadcast to 30 mhz. Both have the same sensitivity and selectivity and most of the same features. Hope that helps.

[@dogtagsvette]

Not sure why, Jon. Even works on my I phone and tablet.

[@gbowne1]

I always wondered how they design the antenna input connections. I heard theres several ways to do that. Perhaps make a video on that.

[@jmic8629]

Hi Pete. Many thanks for the video that is very useful. The only thing is that I didn't catch the exact point where the VTVM should be connected. Can you help me?. Regards.

[@dogtagsvette]

Hi; You can use the S meter for front end alignment but the book says to use pin 2 of V13 and you will need to be set up to measure a minus voltage. Back signal gen down so that you are not in saturation. You need to be able to see changes in the voltage and if you are saturated with too much signal, you won't see the changes. Same goes for the S meter.

[@jmic8629]

Thank you for your reply. I realised that there is a lead with a small loop in that part of the chassis that is not connected to any component. I have connected my digital tester on it and there is negative voltage that is higher when a station is tuned. Has to do something this lead with a sort of prearranged connection to align the receiver? Regards

[@Kennynva]

So what exactly does the IF adjustment do...I am a new to alignment...but just wanted to ask...thanks..If you have time look at the Hallicrafters SX-71 alignment section...I can do the second part..but the IF I dont get...with the built in crystal and all...thanks...

[@dogtagsvette]

Hi; Thanks for the comment. You've made me realize that many don't really have a working knowledge of the superhetrodyne principle and perhaps I should make a video explaining this. If you're already tackling the RF alignment, I'll be it won't take but a few minutes to grasp the concept which should answer your question. I'll post here with a link as soon as I've got something put together.

[@Kennynva]

Why thank you very much...this radio has a 455khz crystal built in...and somehow I suppose to have the BFO on and set the zero beat...then there is a transformer that is suppose to align with this 455khz crystal..which I believe sets the IF alignment..thanks for any info you have..

[@Beretta96Dan]

Pete, I used to have an RCA VTVM, but it has been gone a long time. I have some digital VOM's that have about 50k ohms/volt inputs. I should be able to use them in place of the VTVM. Right? Thanks for the videos...Dan

[@gbowne1]

What's the difference between the 170 and 180?