reported 'DF' should be used in conjonction with 'MAIN' or 'BOTH', but not 'ADF'

[Northwind]

DCS F-5E ADF behavior is different from what is written in the manual( T.O. 1F-5E-1 and DCS F-5E manual).

To use ADF navigation, the DCS F-5E need to rotate the UHF Radio Function Selector to the ADF position and the NAV MODE selector to the DF position.

When the NAV MODE selector in the DF position, the MAIN and BOTH positions of the UHF Radio Function Selector does not activate the ADF navigation.

 

However

 

On T.O. 1F-5E-1,Page 115,item 2 is written:

UHF Radio Function Selector ADF - Relative bearing to tuned station is displayed on HSI. Nonfunctional on aircraft with UHF DF selection on NAV MODE selector.

Page 109,item 8 is written:

Function Selector ADF - Relative bearing to tuned station is displayed on HSI (some aircraft nonfunctional).

Page 116,item 9 is written(Same as DCS F-5E manual,different from DCS F-5E actual behavior):

NAV MODE Selector DF - HSI bearing pointer points to UHF station selected on UHF radio with radio function selector in MAIN or BOTH.

So,ADF position of UHF Radio Function Selector is Nonfunctional on aircraft with UHF DF selection on NAV MODE selector.

This means when the NAV MODE selector in the DF position,the MAIN and BOTH positions of the UHF Radio Function Selector should activate the ADF navigation.The ADF position of the UHF Radio Function Selector is unknown.

 

DCS F-5E with UHF DF selection on NAV MODE selector.

RL F-5E in T.O. 1F-5E-1 and DCS F-5E equipped with the AN/ARC-164 UHF radio, AN/ARA-50 UHF/ADF automatic direction finder,and RL F-5E are equipped AN/ARN-118 TACAN systems(The pictures and examples in the manual are AN/ARN-1 1 8 ),DCS F-5E equipped TACAN AN/ARC(N)-118 NAVIGATION SYSTEM.

 

 

Did I make a mistake? Or DCS F-5E simulates different variant?

Or the behavior of the F-5E ADF does not match the manual( T.O. 1F-5E-1 and DCS F-5E manual).

Edited September 30, 2019 by Northwind

[tom_19d]

Northwind, I think you may have found a problem here. I have always used the ADF by selecting "DF" and "ADF" but that was self taught, I never read the manual carefully. However, I agree with your assessment that according to the TO you should only have to select "DF" and the ADF should be functional with the radio function selector still set at MAIN or BOTH.

 

 

I am away from home but I will test this when I can with the manual open.

[streakeagle]

ADF should be active the moment the NAV mode is placed in DF.

The ADF position on the radio doesn't do anything on aircraft with the NAV mode switch.

 

From 1-103 in the section on TACAN:

 

Edited June 19, 2020 by streakeagle

[PE_Tigar]

I couldn't get ADF to work either way - I was trying to tune ATC UHF frequencies on airports on Persian Gulf map.. nothing with either NAV Mode on DF, UHF function selector on ADF, or both. Am I doing something wrong?

 

EDIT: I actually got it to work, but it's as described in the original post, which is very impractical - since there needs to be some kind of transmission on the frequency to get ADF bearing, I need to set the radio to Main or Both, ask ATC something, then quickly switch to ADF to get the needle to show the direction for a short while... I'd say this is not "as intended".

Edited January 9, 2021 by PE_Tigar

[Golo]

For you to get direction there needs to be a signal on a frequency you are listening to. ATC is not dedicated ADF station that transmit all the time, they obviously only transmit when they are taking to someone in this case its working as intended.

 

[PE_Tigar]

That part is correct, but I have serious doubts that needing to switch UHF Radio Function Selector to ADF to get the signal is "as intended". As others pointed above, manual says you should get ADF bearing with UHF Radio Function Selector on Main or Both; UHF Radio Function Selector ADF position should be non-functional.

[Minsky]

Has it been acknowledged at all?

It's 2025, and the issue still persists in the Remastered model.

[Flappie]

T.O. 1F-5E-1 page 1-99 does not make it very clear. Are both ADF and DF needed, or only DF? I'll keep reading the manual.

EDIT: 

After reading again all of the above in this thread, I agree. DF should suffice to get a a bearing on the HSI. Let me recap before reporting:

• TACAN + MAIN, BOTH or ADF: HSI shows TACAN bearing
• DF + MAIN or BOTH: HSI shows radio beacon bearing
• DF + ADF: HSI shows nothing

 

 

Edited March 17 by Flappie

[Flappie]

I believe the 1984 manual is not to be used here (see rule 1.16), but I managed to find the right sections in the 1978 manual. The inconsistency is now reported.